Toll-like receptor antagonist compounds and methods of use

ABSTRACT

The invention relates to compounds of formula (I): or a salt or solvate thereof, wherein the variables are as described herein. Compounds of formula (I) and pharmaceutical compositions thereof are antagonists of toll-like receptors such as TLR7, TLR8 and/or TLR9 that are useful for inhibiting immune response and treating diseases associated with undesirable immune response.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority benefit to U.S. Provisional PatentApplication Nos. 62/421,140, filed on Nov. 11, 2016, and 62/421,144,filed on Nov. 11, 2016, the disclosures of each of which are herebyincorporated by reference in their entireties.

STATEMENT OF RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSOREDRESEARCH

This invention was made with government support under NIH SBIR grantsR43AI00376-02 and R44AI100376-03 awarded by the National Institutes ofHealth (NIH). The United States government has certain rights in theinvention.

BACKGROUND OF THE INVENTION

Toll-like receptors (TLRs) are a family of transmembrane proteins thatrecognize conserved microbial molecules, referred to aspathogen-associated molecular patterns (PAMPs), which aredistinguishable from host molecules. As such TLRs play important rolesin innate immune responses. TLRs 7, 8 and 9 are nucleic acid sensingTLRs. In addition to recognizing PAMPs, these receptors also recognizeendogenous immune complexes containing self-nucleic acids as well asself-antigens referred to as damage-associated molecular patterns(DAMPs). By recognizing and responding to self-nucleic acids and DAMPsthese receptors have been implicated in certain autoimmune diseaseconditions, including lupus, psoriasis, arthritis and multiplesclerosis, and noninfectious inflammatory disorders includingnon-alcoholic liver disease, non-alcoholic steatohepatitis,acetaminophen-induced hepatotoxicity, and pancreatitis, which inducepro-inflammatory cytokines that contribute to the pathogenesis ofdisease. Activation of TLRs 7, 8 and 9 by immune complexes and DAMPsleads to the expression of inflammatory cytokines such as interleukin(IL)-12, IL-6, tumor necrosis factor alpha (TNF-α), IL-1β, interferon(IFN)-α, and to the induction of IFN-inducible genes (Kandimalla, et al.Nucleic Acids Res. 2013 41:3947-3961).

Agonists and antagonists of TLRs find use in modulating immuneresponses. TLR agonists are typically employed to stimulate immuneresponses, whereas TLR antagonists are typically employed to inhibitimmune responses (Gosu et al., Molecules, 2012, 17:13503-13529).Immunoregulatory nucleic acids, synthetic oligodeoxyribonucleotides, andoligoribonucleotides have been reported as antagonists for TLRs 7, 8 and9. See, e.g., U.S. Pat. Nos. 8,759,305; 8,853,375; and 9,228,184.However, there remains a need for orally bioavailable TLR antagonistsfor therapeutic or prophylactic treatment of TLR-mediated immuneresponses.

BRIEF SUMMARY OF THE INVENTION

Disclosed are heterocyclic compounds that are antagonists of toll-likereceptors such as TLR8 and/or TLR9, compositions containing thesecompounds and methods for inhibiting an immune response such as a TLR8-and/or TLR9-dependent immune response, and methods of treating diseasesassociated with an undesirable immune response.

In one aspect, provided is a compound of formula (I), or any variationthereof, or a salt thereof (e.g., a pharmaceutically acceptable saltthereof), as detailed herein. Also provided is a compound of formula(A-I), (Ia), (I⁰), (I⁰a), (I⁰a-1), (I⁰a-2), (II), (IIa), (IIa-1),(IIa-1a), (IIa-1a-1), (IIa-1a-2), (IIa-1a-3), (IIa-1b), (IIa-1b-1),(IIa-1b-2), (IIa-1b-3), (IIa-1c), (IIa-1c-1), (IIa-1d), (IIa-1d-1),(IIa-1d-2), (IIa-1d-3), (IIa-1e), (IIa-1e-1), (IIa-1e-2), (IIa-1e-3),(IIa-1f), (IIa-1f-1), (IIa-1f-2), (IIa-1f-3), (III), (IIIa), (IV),(IV-a), (IV-a-1), (IV-a-2), (V), (V-a), (V-a-1), (V-a-2), (VI), (VI-a),(VI-a-1), (VI-a-2), (VII), (VII-a), (VII-a-1), (VII-a-2), (VIII),(VIII-a), (VIII-a-1), or (VIII-a-2), or a salt thereof (e.g., apharmaceutically acceptable salt thereof), as detailed herein.

Further provided is a pharmaceutical composition comprising a compoundof formula (I), or any variation thereof detailed herein, or a saltthereof (e.g., a pharmaceutically acceptable salt thereof), and apharmaceutically acceptable excipient.

In another aspect, provided is a method of inhibiting an immune responsein an individual (such as a human) in need thereof comprisingadministering to the individual a therapeutically effective amount of acompound of formula (I), or any variation thereof detailed herein, or apharmaceutically acceptable salt thereof. In some embodiments, theimmune response is TLR8-dependent. In some embodiments, the immuneresponse is TLR9-dependent. In some embodiments, the immune response isTLR8- and TLR9-dependent. In some embodiments, the immune response isassociated with chronic pathogen stimulation or acute pathogenstimulation (e.g., acute pathogen stimulation due to sepsis). In someembodiments, the immune response is associated with an immunologicaldisorder.

Also provided is a method of treating or ameliorating one or moresymptoms of an immunological disorder in an individual (such as a human)in need thereof comprising administering to the individual atherapeutically effective amount of a compound of formula (I), or anyvariation thereof detailed herein, or a pharmaceutically acceptable saltthereof. In some embodiments, the immunological disorder is anautoimmune disease (e.g., systemic lupus erythematosus, type I diabetesmellitus, multiple sclerosis, rheumatoid arthritis, inflammatory boweldisease, Sjogren's syndrome, scleroderma and dermatomyositis). In someembodiments, the immunological disorder is an inflammatory disease(e.g., pancreatitis, kidney fibrosis, liver fibrosis, lung fibrosis,chronic kidney disease, alcohol-related fatty liver disease,non-alcoholic fatty liver disease, and liver cirrhosis).

Further provided is a method of treating cancer in an individual (suchas a human) in need thereof comprising administering to the individual atherapeutically effective amount of a compound of formula (I), or anyvariation thereof detailed herein, or a pharmaceutically acceptable saltthereof. In some embodiments, the cancer is dependent upon activation ofone or both of TLR8 and TLR9. In some embodiments, the cancer isWaldenstrom's macroglobulinemia. In some embodiments, the cancerpossesses an oncogenic mutation in a myeloid differentiation primaryresponse gene 88 (MYD88). In some embodiments, the cancer ishepatocellular carcinoma (HCC).

Also provided is a compound of formula (I), or any variation thereofdetailed herein, or a pharmaceutical composition thereof, for inhibitingan immune response, for the treatment of an immunological disorder(e.g., autoimmune disease, inflammatory disease, chronic or acutepathogen stimulation, etc.), or for the treatment of cancer.

Also provided is use of a compound of formula (I), or any variationthereof detailed herein, or a pharmaceutically acceptable salt thereof,in the manufacture of a medicament for inhibiting an immune response,for treating an immunological disorder, or for treating cancer.

Further provided is a kit comprising a compound of formula (I), or anyvariation thereof detailed herein, or a pharmaceutically acceptable saltthereof. In some embodiments, the kit comprises instructions for useaccording to a method described herein, such as a method of inhibitingimmune response, a method of treating an immunological disorder, or amethod of treating cancer.

In another aspect, provided is a method of making a compound of formula(I) or any variation thereof. Also provided are compound intermediatesuseful in synthesis of a compound of formula (I), or any variationthereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows inhibition of TLR9 activity in mice using Compound No. 5 at5 mg/Kg.

FIG. 2 shows inhibition of TLR9 activity in mice over time followingintra-peritoneal injection of Compound No. 5 at 5 mg/Kg.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides, inter alia, compounds of formula (A-I) or (I),and variations thereof, pharmaceutical compositions comprising compoundsof formula (A-I) or (I), and methods of using such compounds andcompositions for inhibiting TLR8- and/or TLR9-dependent responses,particularly for inhibiting pathological immune responses, or fortreating an immunological disorder or cancer.

Definitions

For use herein, unless clearly indicated otherwise, the terms “a”, “an”and “the” refer to one or more. For example, “an excipient” includes oneor more excipients.

Reference to “about” a value or parameter herein encompasses from 90% to110% of the value or parameter, and includes (and describes) embodimentsthat are directed to that value or parameter per se. For example, adescription referring to “about X” includes description of “X”, as wellas a range of 0.9X to 1.1X.

“Alkyl” as used herein refers to and includes, unless otherwise stated,a saturated linear (i.e., unbranched) or branched univalent hydrocarbonchain or combination thereof, having the number of carbon atomsdesignated (i.e., C₁-C₁₀ means one to ten carbon atoms). Particularalkyl groups are those having 1 to 20 carbon atoms (a “C₁-C₂₀ alkyl”),having 1 to 10 carbon atoms (a “C₁-C₁₀ alkyl”), having 6 to 10 carbonatoms (a “C₆-C₁₀ alkyl”), having 1 to 6 carbon atoms (a “C₁-C₆ alkyl”),having 2 to 6 carbon atoms (a “C₂-C₆ alkyl”), or having 1 to 4 carbonatoms (a “C₁-C₄ alkyl”). Examples of alkyl groups include, but are notlimited to, groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl,t-butyl, isobutyl, sec-butyl, homologs and isomers of, for example,n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, and the like.

“Alkylene” as used herein refers to the same residues as alkyl, buthaving bivalency. Particular alkylene groups are those having 1 to 20carbon atoms (a “C₁-C₂₀ alkylene”), having 1 to 10 carbon atoms (a“C₁-C₁₀ alkylene”), having 6 to 10 carbon atoms (a “C₆-C₁₀ alkylene”),having 1 to 6 carbon atoms (a “C₁-C₆ alkylene”), 1 to 5 carbon atoms (a“C₁-C₅ alkylene”), 1 to 4 carbon atoms (a “C₁-C₄ alkylene”) or 1 to 3carbon atoms (a “C₁-C₃ alkylene”). Examples of alkylene include, but arenot limited to, groups such as methylene (—CH₂—), ethylene (—CH₂CH₂—),propylene (—CH₂CH₂CH₂—), isopropylene (—CH₂CH(CH₃)—), butylene(—CH₂(CH₂)₂CH₂—), isobutylene (—CH₂CH(CH₃)CH₂—), pentylene(—CH₂(CH₂)₃CH₂—), hexylene (—CH₂(CH₂)₄CH₂—), heptylene (—CH₂(CH₂)₅CH₂—),octylene (—CH₂(CH₂)₆CH₂—), and the like.

“Alkenyl” as used herein refers to and includes, unless otherwisestated, an unsaturated linear (i.e., unbranched) or branched univalenthydrocarbon chain or combination thereof, having at least one site ofolefinic unsaturation (i.e., having at least one moiety of the formulaC═C) and having the number of carbon atoms designated (i.e., C₂-C₁₀means two to ten carbon atoms). An alkenyl group may have “cis” or“trans” configurations, or alternatively have “E” or “Z” configurations.Particular alkenyl groups are those having 2 to 20 carbon atoms (a“C₂-C₂₀ alkenyl”), having 2 to 8 carbon atoms (a “C₂-C₈ alkenyl”),having 2 to 6 carbon atoms (a “C₂-C₆ alkenyl”), or having 2 to 4 carbonatoms (a “C₂-C₄ alkenyl”). Examples of alkenyl group include, but arenot limited to, groups such as ethenyl (or vinyl), prop-1-enyl,prop-2-enyl (or allyl), 2-methylprop-1-enyl, but-1-enyl, but-2-enyl,but-3-enyl, buta-1,3-dienyl, 2-methylbuta-1,3-dienyl, homologs andisomers thereof, for example, pent-1-enyl, pent-2-enyl, hex-1-enyl,hex-2-enyl, hex-3-enyl, and the like.

“Alkenylene” as used herein refers to the same residues as alkenyl, buthaving bivalency. Particular alkylene groups are those having 2 to 20carbon atoms (a “C₂-C₂₀ alkenylene”), having 2 to 10 carbon atoms (a“C₂-C₁₀ alkenylene”), having 2 to 6 carbon atoms (a “C₂-C₆ alkenylene”),2 to 4 carbon atoms (a “C₂-C₄ alkenylene”) or 2 to 3 carbon atoms (a“C₂-C₃ alkenylene”). Examples of alkenylene include, but are not limitedto, groups such as ethenylene (or vinylene) (—CH═CH—), propenylene(—CH═CHCH₂—), 1,4-but-1-enylene (—CH═CH—CH₂CH₂—), 1,4-but-2-enylene(—CH₂CH═CHCH₂—), 1,6-hex-1-enylene (—CH═CH—(CH₂)₃CH₂—), and the like.

“Alkynyl” as used herein refers to and includes, unless otherwisestated, an unsaturated linear (i.e., unbranched) or branched univalenthydrocarbon chain or combination thereof, having at least one site ofacetylenic unsaturation (i.e., having at least one moiety of the formulaC≡C) and having the number of carbon atoms designated (i.e., C₂-C₁₀means two to ten carbon atoms). Particular alkynyl groups are thosehaving 2 to 20 carbon atoms (a “C₂-C₂₀ alkynyl”), having 2 to 8 carbonatoms (a “C₂-C₈ alkynyl”), having 2 to 6 carbon atoms (a “C₂-C₆alkynyl”), or having 2 to 4 carbon atoms (a “C₂-C₄ alkynyl”). Examplesof alkynyl group include, but are not limited to, groups such as ethynyl(or acetylenyl), prop-1-ynyl, prop-2-ynyl (or propargyl), but-1-ynyl,but-2-ynyl, but-3-ynyl, homologs and isomers thereof, and the like.

“Alkynylene” as used herein refers to the same residues as alkynyl, buthaving bivalency. Particular alkylene groups are those having 2 to 20carbon atoms (a “C₂-C₂₀ alkynylene”), having 2 to 10 carbon atoms (a“C₂-C₁₀ alkynylene”), having 2 to 6 carbon atoms (a “C₂-C₆ alkynylene”),2 to 4 carbon atoms (a “C₂-C₄ alkynylene”) or 2 to 3 carbon atoms (a“C₂-C₃ alkynylene”). Examples of alkynylene include, but are not limitedto, groups such as ethynylene (or acetylenylene) (—C≡C—), propynylene(—C≡CCH₂—), and the like.

“Cycloalkyl” as used herein refers to and includes, unless otherwisestated, saturated cyclic univalent hydrocarbon structures, having thenumber of carbon atoms designated (i.e., C₃-C₁₀ means three to tencarbon atoms). Cycloalkyl can consist of one ring, such as cyclohexyl,or multiple rings, such as adamantyl. A cycloalkyl comprising more thanone ring may be fused, spiro or bridged, or combinations thereof.Particular cycloalkyl groups are those having from 3 to 12 annularcarbon atoms. A preferred cycloalkyl is a cyclic hydrocarbon having from3 to 8 annular carbon atoms (a “C₃-C₈ cycloalkyl”), having 3 to 6annular carbon atoms (a “C₃-C₆ cycloalkyl”), or having from 3 to 4annular carbon atoms (a “C₃-C₄ cycloalkyl”). Examples of cycloalkylinclude, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, cycloheptyl, norbornyl, and the like.

“Cycloalkylene” as used herein refers to the same residues ascycloalkyl, but having bivalency. Cycloalkylene can consist of one ringor multiple rings which may be fused, spiro or bridged, or combinationsthereof. Particular cycloalkylene groups are those having from 3 to 12annular carbon atoms. A preferred cycloalkylene is a cyclic hydrocarbonhaving from 3 to 8 annular carbon atoms (a “C₃-C₈ cycloalkylene”),having 3 to 6 annular carbon atoms (a “C₃-C₆ cycloalkylene”), or havingfrom 3 to 4 annular carbon atoms (a “C₃-C₄ cycloalkylene”). Examples ofcycloalkylene include, but are not limited to, cyclopropylene,cyclobutylene, cyclopentylene, cyclohexylene, cycloheptylene,norbornylene, and the like. A cycloalkylene may attach to the parentstructure twice via the same ring carbon atom or via two different ringcarbon atoms. When a cycloalkylene attaches to the remaining structuresvia two different ring carbon atoms, the connecting bonds may be cis- ortrans- to each other. For example, cyclobutylene may include1,1-cyclobutylene, 1,2-cyclobutylene and 1,3-cyclobutylene (e.g.,cis-1,3-cyclobutylene or trans-1,3-cyclobutylene), or mixture thereof.

“Cycloalkenyl” refers to and includes, unless otherwise stated, anunsaturated cyclic non-aromatic univalent hydrocarbon structures, havingat least one site of olefinic unsaturation (i.e., having at least onemoiety of the formula C=C) and having the number of carbon atomsdesignated (i.e., C₂-C₁₀ means two to ten carbon atoms). Cycloalkenylcan consist of one ring, such as cyclohexenyl, or multiple rings, suchas norbornenyl. A preferred cycloalkenyl is an unsaturated cyclichydrocarbon having from 3 to 8 annular carbon atoms (a “C₃-C₈cycloalkenyl”). Examples of cycloalkenyl groups include, but are notlimited to, cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl,norbornenyl, and the like.

“Cycloalkenylene” as used herein refers to the same residues ascycloalkenyl, but having bivalency.

“Aryl” as used herein refers to an unsaturated aromatic carbocyclicgroup having a single ring (e.g., phenyl) or multiple condensed rings(e.g., naphthyl or anthryl) which condensed rings may or may not bearomatic. Particular aryl groups are those having from 6 to 14 annularcarbon atoms (a “C₆-C₁₄ aryl”). An aryl group having more than one ringwhere at least one ring is non-aromatic may be connected to the parentstructure at either an aromatic ring position or at a non-aromatic ringposition. In one variation, an aryl group having more than one ringwhere at least one ring is non-aromatic is connected to the parentstructure at an aromatic ring position.

“Arylene” as used herein refers to the same residues as aryl, but havingbivalency. Particular arylene groups are those having from 6 to 14annular carbon atoms (a “C₆-C₁₄ arylene”).

“Heteroaryl” as used herein refers to an unsaturated aromatic cyclicgroup having from 1 to 14 annular carbon atoms and at least one annularheteroatom, including but not limited to heteroatoms such as nitrogen,oxygen and sulfur. A heteroaryl group may have a single ring (e.g.,pyridyl, imidazolyl) or multiple condensed rings (e.g., indolizinyl,pyrazolo-pyridazinyl) where at least one of the condensed rings isaromatic. Particular heteroaryl groups are 5 to 14-membered rings having1 to 12 annular carbon atoms and 1 to 6 annular heteroatomsindependently selected from nitrogen, oxygen and sulfur, 5 to10-membered rings having 1 to 8 annular carbon atoms and 1 to 4 annularheteroatoms independently selected from nitrogen, oxygen and sulfur, or5, 6 or 7-membered rings having 1 to 5 annular carbon atoms and 1 to 4annular heteroatoms independently selected from nitrogen, oxygen andsulfur. In one variation, heteroaryl includes monocyclic aromatic 5-, 6-or 7-membered rings having from 1 to 6 annular carbon atoms and 1 to 4annular heteroatoms independently selected from nitrogen, oxygen andsulfur. In another variation, heteroaryl includes polycyclic aromaticrings having from 1 to 12 annular carbon atoms and 1 to 6 annularheteroatoms independently selected from nitrogen, oxygen and sulfur. Aheteroaryl group having more than one ring where at least one ring isnon-aromatic may be connected to the parent structure at either anaromatic ring position or at a non-aromatic ring position. In onevariation, a heteroaryl group having more than one ring where at leastone ring is non-aromatic is connected to the parent structure at anaromatic ring position.

“Heteroarylene” as used herein refers to the same residues asheteroaryl, but having bivalency.

“Heterocycle”, “heterocyclic”, or “heterocyclyl” as used herein refersto a saturated or an unsaturated non-aromatic cyclic group having asingle ring or multiple condensed rings, and having from 1 to 14 annularcarbon atoms and from 1 to 6 annular heteroatoms, such as nitrogen,sulfur or oxygen, and the like. A heterocycle comprising more than onering may be fused, bridged or spiro, or any combination thereof. Infused ring systems, one or more of the fused rings can be cycloalkyl orcycloalkenyl. The heterocyclyl group may be optionally substitutedindependently with one or more substituents described herein. Particularheterocyclyl groups are 3 to 14-membered rings having 1 to 13 annularcarbon atoms and 1 to 6 annular heteroatoms independently selected fromnitrogen, oxygen and sulfur, 3 to 12-membered rings having 1 to 11annular carbon atoms and 1 to 6 annular heteroatoms independentlyselected from nitrogen, oxygen and sulfur, 3 to 10-membered rings having1 to 9 annular carbon atoms and 1 to 4 annular heteroatoms independentlyselected from nitrogen, oxygen and sulfur, 3 to 8-membered rings having1 to 7 annular carbon atoms and 1 to 4 annular heteroatoms independentlyselected from nitrogen, oxygen and sulfur, or 3 to 6-membered ringshaving 1 to 5 annular carbon atoms and 1 to 4 annular heteroatomsindependently selected from nitrogen, oxygen and sulfur. In onevariation, heterocyclyl includes monocyclic 3-, 4-, 5-, 6- or 7-memberedrings having from 1 to 2, 1 to 3, 1 to 4, 1 to 5 or 1 to 6 annularcarbon atoms and 1 to 2, 1 to 3 or 1 to 4 annular heteroatomsindependently selected from nitrogen, oxygen and sulfur. In anothervariation, heterocyclyl includes polycyclic non-aromatic rings havingfrom 1 to 12 annular carbon atoms and 1 to 6 annular heteroatomsindependently selected from nitrogen, oxygen and sulfur.

“Heterocyclylene” as used herein refers to the same residues asheterocyclyl, but having bivalency.

“Halo” or “halogen” refers to elements of the Group 17 series havingatomic number 9 to 85. Preferred halo groups include the radicals offluorine, chlorine, bromine and iodine. Where a residue is substitutedwith more than one halogen, it may be referred to by using a prefixcorresponding to the number of halogen moieties attached. For example,dihaloaryl, dihaloalkyl, trihaloaryl etc. refer to aryl and alkylsubstituted with two (“di”) or three (“tri”) halo groups, which may bebut are not necessarily the same halogen; thus 4-chloro-3-fluorophenylis within the scope of dihaloaryl. An alkyl group in which each hydrogenis replaced with a halo group is referred to as a “perhaloalkyl.” Apreferred perhaloalkyl group is trifluoroalkyl (—CF₃). Similarly,“perhaloalkoxy” refers to an alkoxy group in which a halogen takes theplace of each H in the hydrocarbon making up the alkyl moiety of thealkoxy group. An example of a perhaloalkoxy group is trifluoromethoxy(—OCF₃).

“Carbonyl” refers to the group C═O.

“Thiocarbonyl” refers to the group C═S.

“Oxo” refers to the moiety ═O.

“Optionally substituted” unless otherwise specified means that a groupmay be unsubstituted or substituted by one or more (e.g., 1, 2, 3, 4 or5) of the substituents listed for that group in which the substituentsmay be the same of different. In one embodiment, an optionallysubstituted group has one substituent. In another embodiment, anoptionally substituted group has two substituents. In anotherembodiment, an optionally substituted group has three substituents. Inanother embodiment, an optionally substituted group has foursubstituents. In some embodiments, an optionally substituted group has 1to 2, 1 to 3, 1 to 4 or 1 to 5 substituents.

Unless a specific isotope of an element is indicated in a formula, theinvention includes all isotopologues of the compounds disclosed herein,such as, for example, deuterated derivatives of the compounds (where Hcan be ²H, i.e., D). Isotopologues can have isotopic replacements at anyor at all locations in a structure, or can have atoms present in naturalabundance at any or all locations in a structure.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination. All combinations of the embodimentspertaining to the chemical groups represented by the variables arespecifically embraced by the present invention and are disclosed hereinjust as if each and every combination was individually and explicitlydisclosed, to the extent that such combinations embrace compounds thatare stable compounds (i.e., compounds that can be isolated,characterized, and tested for biological activity). In addition, allsubcombinations of the chemical groups listed in the embodimentsdescribing such variables are also specifically embraced by the presentinvention and are disclosed herein just as if each and every suchsubcombination of chemical groups was individually and explicitlydisclosed herein.

It is understood that aspects and embodiments described herein as“comprising” include “consisting of” and “consisting essentially of”embodiments.

As used herein and in the appended claims, the singular forms “a”, “an”,and “the” include plural referents unless otherwise indicated or clearfrom context.

Unless clearly indicated otherwise, the term “about” is used to indicatethat a value includes the standard deviation of error for the device ormethod being employed to determine the value. Reference to “about” avalue or parameter herein includes (and describes) embodiments that aredirected to that value or parameter per se. For example, descriptionreferring to “about X” includes description of “X.”

The term “individual” as used herein refers to a mammal, including butnot limited to a human, non-human primate, cow, horse, cat, dog, orrodent. In one variation, the individual is a human.

As used herein, “treatment” or “treating” is an approach for obtainingbeneficial or desired results including clinical results. For purposesof this invention, beneficial or desired results include, but are notlimited to, one or more of the following: decreasing one more symptomsresulting from the disease, diminishing the extent of the disease,stabilizing the disease (e.g., preventing or delaying the worsening ofthe disease), preventing or delaying the spread of the disease, delayingthe occurrence or recurrence of the disease, delay or slowing theprogression of the disease, ameliorating the disease state, providing aremission (whether partial or total) of the disease, decreasing the doseof one or more other medications required to treat the disease,enhancing effect of another medication, delaying the progression of thedisease, increasing the quality of life, and/or prolonging survival.Thus, “treating” or “treatment” does not require complete alleviation ofsigns or symptoms, does not require a cure, and specifically includesprotocols that have only a palliative effect on the individual. Further,“treating” and “treatment” do not necessarily occur by administration ofone dose, but often occur upon administration of a series of doses.

As used herein, the term “effective amount” refers to an amount of acompound of the invention sufficient to carry out a specifically statedpurpose. As is understood in the art, an effective amount of a giventherapeutic form may be in one or more doses, i.e., a single dose ormultiple doses may be required to achieve the desired treatmentendpoint. An effective amount may be considered in the context ofadministering one or more therapeutic agents (e.g., a compound, orpharmaceutically acceptable salt thereof), and a single agent may beconsidered to be given in an effective amount if, in conjunction withone or more other agents, a desirable or beneficial result may be or isachieved. Suitable doses of any of the co-administered compounds mayoptionally be lowered due to the combined action (e.g., additive orsynergistic effects) of the compounds.

A “therapeutically effective amount” refers to an amount of a compoundor salt thereof sufficient to produce a desired therapeutic outcome.

As used herein, “unit dosage form” refers to physically discrete units,suitable as unit dosages, each unit containing a predetermined quantityof active ingredient calculated to produce the desired therapeuticeffect in association with the required pharmaceutical excipient. Unitdosage forms may contain a single or a combination therapy.

As used herein, by “pharmaceutically acceptable” or “pharmacologicallyacceptable” is meant a material that is not biologically or otherwiseundesirable, e.g., the material may be incorporated into apharmaceutical composition administered to a patient without causing anysignificant undesirable biological effects or interacting in adeleterious manner with any of the other components of the compositionin which it is contained. Pharmaceutically acceptable excipients havepreferably met the required standards of toxicological and manufacturingtesting and/or are included on the Inactive Ingredient Guide prepared bythe U.S. Food and Drug administration.

“Pharmaceutically acceptable salts” are those salts which retain atleast some of the biological activity of the free (non-salt) compoundand which can be administered as drugs or pharmaceuticals to anindividual. Such salts, for example, include: (1) acid addition salts,formed with inorganic acids such as hydrochloric acid, hydrobromic acid,sulfuric acid, nitric acid, phosphoric acid, and the like; or formedwith organic acids such as acetic acid, oxalic acid, propionic acid,succinic acid, maleic acid, tartaric acid and the like; (2) salts formedwhen an acidic proton present in the parent compound either is replacedby a metal ion, e.g., an alkali metal ion, an alkaline earth ion, or analuminum ion; or coordinates with an organic base. Acceptable organicbases include ethanolamine, diethanolamine, triethanolamine, and thelike. Acceptable inorganic bases include aluminum hydroxide, calciumhydroxide, potassium hydroxide, sodium carbonate, sodium hydroxide, andthe like. Pharmaceutically acceptable salts can be prepared in situ inthe manufacturing process, or by separately reacting a purified compoundof the invention in its free acid or base form with a suitable organicor inorganic base or acid, respectively, and isolating the salt thusformed during subsequent purification.

The term “excipient” as used herein means an inert or inactive substancethat may be used in the production of a drug or pharmaceutical, such asa tablet containing a compound of the invention as an active ingredient.Various substances may be embraced by the term excipient, includingwithout limitation any substance used as a binder, disintegrant,coating, compression/encapsulation aid, cream or lotion, lubricant,solutions for parenteral administration, materials for chewable tablets,sweetener or flavoring, suspending/gelling agent, or wet granulationagent. Binders include, e.g., carbomers, povidone, xanthan gum, etc.;coatings include, e.g., cellulose acetate phthalate, ethylcellulose,gellan gum, maltodextrin, enteric coatings, etc.;compression/encapsulation aids include, e.g., calcium carbonate,dextrose, fructose dc (dc=“directly compressible”), honey dc, lactose(anhydrate or monohydrate; optionally in combination with aspartame,cellulose, or microcrystalline cellulose), starch dc, sucrose, etc.;disintegrants include, e.g., croscarmellose sodium, gellan gum, sodiumstarch glycolate, etc.; creams or lotions include, e.g., maltodextrin,carrageenans, etc.; lubricants include, e.g., magnesium stearate,stearic acid, sodium stearyl fumarate, etc.; materials for chewabletablets include, e.g., dextrose, fructose dc, lactose (monohydrate,optionally in combination with aspartame or cellulose), etc.;suspending/gelling agents include, e.g., carrageenan, sodium starchglycolate, xanthan gum, etc.; sweeteners include, e.g., aspartame,dextrose, fructose dc, sorbitol, sucrose dc, etc.; and wet granulationagents include, e.g., calcium carbonate, maltodextrin, microcrystallinecellulose, etc.

The term “immune response” as used herein refers to a reaction by cells(e.g., dendritic cells, monocytes, B cells, etc.) of the immune systemto a stimulus (e.g., injury, infection, vaccination, etc.). An exemplaryTLR7-dependent immune response is characterized by secretion ofinterferon-alpha by plasmacytoid dendritic cells in reaction toheat-inactivated influenza virus. An exemplary TLR8-dependent immuneresponse is characterized by secretion of one or both of tumor-necrosisfactor-alpha and interleukin-1 beta by monocytes in reaction to RNA(e.g., ORN8L or released from damaged joint tissue in rheumatoidarthritis). An exemplary TLR9-dependent immune response is characterizedby secretion of interleukin-6 by B cells in reaction to CpG containingDNA (e.g., 1018 ISS or bacterially-derived DNA during infection). Afurther exemplary TLR9-dependent immune response is characterized bysecretion of interleukin-12 by various immune cells in reaction to CpGcontaining DNA (e.g., 1018 ISS or bacterially-derived DNA duringinfection).

The terms “disease” and “disorder” are used interchangeably herein torefer to an abnormal physical condition, which is typicallycharacterized by distinguishing signs and symptoms. For instance, signsand symptoms of diabetes mellitus type 1 include but are not limited tohyperglycemia, frequent urination, and increased thirst.

The terms “immunological disorder” and “immune disorder” are usedinterchangeably herein to refer to a dysfunction of the immune system.In some embodiments of the present disclosure, the immunologicaldisorder is characterized by an overactive and/or misdirected immuneresponse.

As used herein, the term “autoimmune disease” refers to a disorder inwhich the immune system overreacts to a self antigen of an individual.For example, Graves' disease is an autoimmune disease characterized bydevelopment of auto-antibodies to thyroid stimulating hormone.

As used herein, the term “inflammatory disease” refers to a disorder inwhich the immune system overreacts in the absence of an identifiableautoimmune or infectious stimulus. For example, atherosclerosis is aninflammatory disease characterized by thickening of artery walls as aresult of accumulation of white blood cells.

The terms “immunostimulatory sequence” and “ISS” refer to a nucleic acidsequence that stimulates a measurable immune response (e.g., measured invitro, in vivo, and/or ex vivo). For the purpose of the presentdisclosure, the term ISS refers to a nucleic acid sequence comprising anunmethylated CG dinucleotide. Examples of measurable immune responsesinclude, but are not limited to, antigen-specific antibody production,cytokine secretion, lymphocyte activation and lymphocyte proliferation.

“Stimulation” of a response includes eliciting and/or enhancing theresponse when compared to an otherwise identical condition except for aparameter of interest or as compared to another condition (e.g.,increase in TLR-signaling in the presence of a TLR agonist as comparedto the absence of the TLR agonist). For example, “stimulation” of animmune response means a measurable increase in the immune response.

“Inhibition” of a response includes blocking and/or suppressing theresponse when compared to an otherwise identical condition except for aparameter of interest or as compared to another condition (e.g.,decrease in TLR-signaling in the presence of a TLR agonist and a TLRantagonist as compared to the presence of the TLR agonist in the absenceof the TLR antagonist). For example, “inhibition” of an immune responsemeans a measurable decrease in the immune response.

Compounds

The present disclosure provides a compound of formula (A-I):

or a salt or solvate thereof, wherein A¹, A², A³, A⁴, A⁵, R¹, R³, R⁶,R⁷, R⁸, R⁹, U, V, W, X, Y, Z, i, j, m, and n are as detailed herein. Inthe compound of formula (A-I), ring A is a bicyclic heteroarylcontaining 2 to 4 ring nitrogen atoms, and ring B is a 3- to 7-memberedheterocycle containing 1 or 2 ring nitrogen atoms. One ring nitrogenatom of ring B is attached to ring A via an optional linker U. In oneembodiment, U is a bond or absent. A compound of formula (A-I) furthercomprises a moiety —C(O)—[N(R⁷)—W—X—Y]_(m)—N(R⁸)R⁹, which is attached toring B at a carbon atom or a second optional ring nitrogen atom via anoptional linker V, and includes a basic nitrogen (e.g., an amine or aring nitrogen of a heterocycle or heteroaryl group). The—[N(R⁷)—W—X—Y]_(m)—N(R⁸)R⁹ moiety may be a linear chain, a ring ormultiple rings, or a combination thereof. For example, R⁷ and R⁸ may becombined, R⁸ and R⁹ may be combined, or any one of the side chains of W(where present), X and Y may be combined with R⁷, R⁸, or a side chain ofanother one of W (where present), X and Y to form a ring. The —N(R⁸)R⁹moiety may also be combined with Y, with Y and X, or with Y, X and W(where present) to form a heteroaryl group (e.g., an imidazole or apyridyl group). In some preferred embodiments, the terminal nitrogenatom (attached to R⁸, R⁹ and Y) is not attached to anelectron-withdrawing group (e.g., a carbonyl group, an aryl orheteroaryl group) that diminishes the basicity of the basic nitrogenatom, which may be important for the biological activities for thecompound.

In one aspect, provided is a compound of formula (A-I):

or a salt or solvate thereof, wherein:

A¹ is C or N;

A² is CR, N or NR^(2a);

A³ is CR³⁰, N or NR^(3a);

A⁴ is N or CR⁴;

A⁵ is N or CR⁵;

provided that two, three or four of A¹, A², A³, A⁴ and A⁵ are N; whereinthe dashed lines indicate partial or delocalized bonds in an aromaticring;

i and j are independently 0, 1 or 2;

Z is CH or N;

m is 0 or 1;

R¹ is C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl, 5-10-memberedheteroaryl or 3-12-membered heterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl and 3-12-memberedheterocyclyl are independently optionally substituted by R^(10A);

each R², R³, R³⁰, R⁴ and R⁵ is independently hydrogen, halogen, C₁-C₆alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or3-12-membered heterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl,C₆-C₁₄ aryl, 5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A);

each R^(2a) and R^(3a) is independently hydrogen, C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or 3-12-memberedheterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A);

each R⁶, where present, is independently C₁-C₆ alkyl optionallysubstituted by R^(10A);

n is 0, 1, 2, 3 or 4;

U is a bond or methylene optionally substituted by R¹⁰;

V is a bond or C₁-C₂ alkylene optionally substituted by R¹⁰;

W is a bond or C₁-C₄ alkylene optionally substituted by one or both ofR^(W1) and R^(W2);

X is —CR^(X1)R^(X2)—;

Y is —CR^(Y1)R^(Y2)—;

R⁷ is hydrogen, C₁-C₆ alkyl, or taken together with R⁸ to form anethylene optionally substituted by R¹⁰, or taken together with R^(Y1),R^(X1) or R^(W1), where present, to form a C₁-C₆ alkylene optionallysubstituted by R¹⁰;

R⁸ is hydrogen, C₁-C₆ alkyl optionally substituted by R¹⁰, C₆-C₁₄ aryl,5-10-membered heteroaryl, or taken together with R⁷ to form an ethyleneoptionally substituted by R¹⁰, or taken together with R^(Y1), R^(Y2),R^(X1), R^(X2) or R^(W1), where present, to form a C₁-C₆ alkyleneoptionally substituted by R¹⁰, or taken together with R¹⁰, wherepresent, to form a C₁-C₆ alkylene, or taken together with R⁹ and thenitrogen atom to which they are attached to form a 3-12-memberedheterocyclyl optionally substituted by R¹⁰ or a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(Y1), R^(Y2), R⁹and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R10, or taken together with R^(X1),R^(X2), R^(Y1), R^(Y2), R⁹ and the atoms to which they are attached toform a 5-10-membered heteroaryl optionally substituted by R10, or takentogether with R^(W1), R^(W2), where present, R^(X1), R^(X2), R^(Y1),R^(Y2), R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰;

R⁹ is hydrogen, C₁-C₆ alkyl optionally substituted by R¹⁰, or takentogether with R⁸ and the nitrogen atom to which they are attached toform a 3-12-membered heterocyclyl optionally substituted by R¹⁰ or a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(Y1), R^(Y2), R⁸ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(W1), R^(W2),where present, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰;

R^(W1), where present, is C₁-C₆ alkyl optionally substituted by R^(10A),or taken together with R⁷, R⁸, R^(X1) or R^(Y1) to form a C₁-C₆ alkyleneoptionally substituted by Rio, or taken together with R^(W2), R^(X1),R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attachedto form a 5-10-membered heteroaryl optionally substituted by R¹⁰;

R^(W2), where present, is C₁-C₆ alkyl optionally substituted by R^(10A),or taken together with R^(W1), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰;

R^(X1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R⁷, R⁸, R^(Y1) or R^(W1), where present, to form aC₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attachedto form a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(W1), R^(W2), where present, R^(X2), R^(Y1),R^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰;

R^(X2) is hydrogen or C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R^(X1), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms towhich they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰, or taken together with R^(W1), R^(W2), wherepresent, R^(X1), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R⁸ to form a C₁-C₆ alkylene optionallysubstituted by R¹⁰;

R^(Y1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R⁷, R⁸, R^(X1) or R^(W1), where present, to form aC₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(X1), R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X)1,R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰; R^(Y2) ishydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), or takentogether with R^(Y1), R⁸, R⁹ and the atoms to which they are attached toform a 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(X1), R^(X2), R^(Y1), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(X2), R^(Y1), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R⁸ to form a C₁-C₆ alkylene optionally substituted by R¹⁰;

each R¹⁰ is independently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl,C₃-C₈ cycloalkyl, 3-12-membered heterocyclyl, 5-10-membered heteroaryl,C₆-C₁₄ aryl, halogen, —CN, —OR¹¹, —SR¹¹, —NR¹²R¹³, —NO₂, —C═NH(OR¹¹),—C(O)R¹¹, —OC(O)R¹¹, —C(O)OR¹¹, —C(O)NR¹²R¹³, —NR¹¹C(O)R¹²,—NR¹¹C(O)OR¹², —NR¹¹C(O)NR¹²R¹³, —S(O)R¹¹, —S(O)₂R¹¹, —NR¹¹S(O)R¹²,—NR¹¹S(O)₂R¹², —S(O)NR¹²R¹³, —S(O)₂NR¹²R¹³, or —P(O)(OR¹²) (OR¹³);wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl,3-12-membered heterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl ofR¹⁰ are independently optionally substituted by halogen, —CN, oxo,—OR¹⁴, —SR¹⁴, —NR¹⁴R¹⁵, —C(O)R¹⁴, —C(O)OR¹⁴, —S(O)R¹⁴, —S(O)₂R¹⁴,—P(O)(OR¹⁴)(OR¹⁵), 3-12-membered heterocyclyl, 5-10-membered heteroaryl,C₆-C₁₄ aryl, C₃-C₈ cycloalkyl, or C₁-C₆ alkyl optionally substituted byoxo, —OH or halogen, or is taken together with R⁸ to form a C₁-C₆alkylene;

each R^(10A) is independently oxo or R¹⁰;

R¹¹ is independently hydrogen, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl, 5-6-membered heteroaryl or3-6-membered heterocyclyl, wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl, 5-6-membered heteroaryl and3-6-membered heterocyclyl of R¹¹ are independently optionallysubstituted by halogen, oxo, —CN, —OR¹⁶, —NR¹⁶R¹⁷, —P(O)(OR¹⁶)(OR¹⁷), orC₁-C₆ alkyl optionally substituted by halogen, —OH or oxo;

R¹² and R¹³ are each independently hydrogen, C₁-C₆ alkyl, C₂-C₆ alkenyl,C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl, 5-6-membered heteroaryl or3-6 membered heterocyclyl, wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl, 5-6-membered heteroaryl and 3-6membered heterocyclyl of R¹² and R¹³ are independently optionallysubstituted by halogen, oxo, —CN, —OR¹⁶, —NR¹⁶R¹⁷ or C₁-C₆ alkyloptionally substituted by halogen, —OH or oxo;

-   -   or R¹² and R¹³ are taken together with the atom to which they        attached to form a 3-6 membered heterocyclyl optionally        substituted by halogen, oxo, —OR¹⁶, —NR¹⁶R¹⁷ or C₁-C₆ alkyl        optionally substituted by halogen, oxo or —OH;

R¹⁴ and R¹⁵ are each independently hydrogen, C₁-C₆ alkyl optionallysubstituted by halogen or oxo, C₂-C₆ alkenyl optionally substituted byhalogen or oxo, or C₂-C₆ alkynyl optionally substituted by halogen oroxo;

-   -   or R¹⁴ and R¹⁵ are taken together with the atom to which they        attached to form a 3-6 membered heterocyclyl optionally        substituted by halogen, oxo or C₁-C₆ alkyl optionally        substituted by halogen or oxo; and

R¹⁶ and R¹⁷ are each independently hydrogen, C₁-C₆ alkyl optionallysubstituted by halogen or oxo, C₂-C₆ alkenyl optionally substituted byhalogen or oxo, or C₂-C₆ alkynyl optionally substituted by halogen oroxo;

or R¹⁶ and R¹⁷ are taken together with the atom to which they attachedto form a 3-6 membered heterocyclyl optionally substituted by halogen,oxo or C₁-C₆ alkyl optionally substituted by oxo or halogen.

In some embodiments of the compound of formula (A-I), Z is C. In onevariation, ring B is a piperidine ring. In other embodiments of thecompound of formula (A-I), Z is N. In one variation, ring B is apiperazine ring.

In some embodiments of the compound of formula (A-I), m is 1. In otherembodiments, m is 0. In some embodiments, m is 0 and the—[N(R⁷)—W—X—Y]_(m)—N(R⁸)R⁹ moiety is —NH(R⁸) or NH(R⁹). In onevariation, —NH(R⁸) or NH(R⁹) is

In one aspect, the present disclosure provides a compound of formula(I):

or a salt or solvate thereof, wherein A¹, A², A³, A⁴, A⁵, R¹, R³, R⁶,R⁷, R⁸, R⁹, U, V, W, X, Y, i, j, and n are as detailed herein. In thecompound of formula (I), ring A is a bicyclic heteroaryl containing 2 to4 ring nitrogen atoms, and ring B is a 3- to 7-membered heterocyclecontaining one ring nitrogen atom. The ring nitrogen atom of ring B isattached to ring A via an optional linker U. In one embodiment, U is abond or absent. A compound of formula (I) further comprises a carboxyamide moiety, the carboxy end of which is attached to ring B via anoptional linker V, and the amide end of which is tethered to a basicnitrogen (e.g., an amine or a ring nitrogen of a heterocycle orheteroaryl group) via a linking moiety of the formula “—W—X—Y-”. The—N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety may be a linear chain, a ring or multiplerings, or a combination thereof. For example, R⁷ and R⁸ may be combined,R⁸ and R⁹ may be combined, or any one of the side chains of W (wherepresent), X and Y may be combined with R⁷, R⁸, or a side chain ofanother one of W (where present), X and Y to form a ring. The —N(R⁸)R⁹moiety may also be combined with Y, with Y and X, or with Y, X and W(where present) to form a heteroaryl group (e.g., an imidazole or apyridyl group). In some preferred embodiments, the terminal nitrogenatom (attached to R⁸, R⁹ and Y) is not attached to anelectron-withdrawing group (e.g., a carbonyl group, an aryl orheteroaryl group) that diminishes the basicity of the basic nitrogenatom, which may be important for the biological activities for thecompound.

In one aspect, the compound of formula (A-I) is a compound of formula(I):

or a salt or solvate thereof, wherein:

A¹ is C or N;

A² is CR², N or NR^(2a);

A³ is CR³⁰, N or NR^(3a);

A⁴ is N or CR⁴;

A⁵ is N or CR⁵;

provided that two, three or four of A¹, A², A³, A⁴ and A⁵ are N; whereinthe dashed lines indicate partial or delocalized bonds in an aromaticring;

i and j are independently 0, 1 or 2;

R¹ is C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl, 5-10-memberedheteroaryl or 3-12-membered heterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl and 3-12-memberedheterocyclyl are independently optionally substituted by R^(10A);

each R², R³, R³⁰, R⁴ and R⁵ is independently hydrogen, halogen, C₁-C₆alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or3-12-membered heterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl,C₆-C₁₄ aryl, 5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A);

each R^(2a) and R^(3a) is independently hydrogen, C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or 3-12-memberedheterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A).

each R⁶, where present, is independently C₁-C₆ alkyl optionallysubstituted by R^(10A);

n is 0, 1, 2, 3 or 4;

U is a bond or methylene optionally substituted by R¹⁰;

V is a bond or C₁-C₂ alkylene optionally substituted by R¹⁰;

W is a bond or C₁-C₄ alkylene optionally substituted by one or both ofR^(W1) and R^(W2);

X is —CR^(X1)R^(X2)—;

Y is —CR^(Y1)R^(Y2)—;

R⁷ is hydrogen, C₁-C₆ alkyl, or taken together with R⁸ to form anethylene optionally substituted by R¹⁰, or taken together with R^(Y1),R^(X1) or R^(W1), where present, to form a C₁-C₆ alkylene optionallysubstituted by R¹⁰;

R⁸ is hydrogen, C₁-C₆ alkyl optionally substituted by R¹⁰, C₆-C₁₄ aryl,5-10-membered heteroaryl, or taken together with R⁷ to form an ethyleneoptionally substituted by R¹⁰, or taken together with R^(Y1), R^(Y2),R^(X1), R^(X2) or R^(W1), where present, to form a C₁-C₆ alkyleneoptionally substituted by R¹⁰, or taken together with R¹⁰, wherepresent, to form a C₁-C₆ alkylene, or taken together with R⁹ and thenitrogen atom to which they are attached to form a 3-12-memberedheterocyclyl optionally substituted by R¹⁰ or a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(Y1), R^(Y2), R⁹and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, or taken together with R^(X1),R^(X2), R^(Y1), R^(Y2), R⁹ and the atoms to which they are attached toform a 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(W1), R^(W2), where present, R^(X1), R^(X2), R^(Y1),R^(Y2), R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰;

R⁹ is hydrogen, C₁-C₆ alkyl optionally substituted by R¹⁰, or takentogether with R⁸ and the nitrogen atom to which they are attached toform a 3-12-membered heterocyclyl optionally substituted by R¹⁰ or a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(Y1), R^(Y2), R⁸ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byRio, or taken together with R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(W1), R^(W2),where present, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰; R^(W1), where present, is C₁-C₆ alkyl optionallysubstituted by R^(10A), or taken together with R⁷, R⁸, R^(X1) or R^(Y1)to form a C₁-C₆ alkylene optionally substituted by R¹⁰, or takentogether with R^(W2), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰;

R^(W2), where present, is C₁-C₆ alkyl optionally substituted by R^(10A),or taken together with R^(W1), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰;

R^(X1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R⁷, R⁸, R^(Y1) or R^(W1), where present, to form aC₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attachedto form a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(W1), R^(W2), where present, R^(X2), R^(Y1),R^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰;

R^(X2) is hydrogen or C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R^(X1), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms towhich they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰, or taken together with R^(W1), R^(W2), wherepresent, R^(X1), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R⁸ to form a C₁-C₆ alkylene optionallysubstituted by R¹⁰;

R^(Y1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R⁷, R⁸, R^(X1) or R^(W1), where present, to form aC₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(X1), R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰;

R^(Y2) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R^(Y1), R⁸, R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R^(X1), R^(X2), R^(Y1), R⁸, R⁹ and the atomsto which they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰, or taken together with R^(W1), R^(W2), wherepresent, R^(X1), R^(X2), R^(Y1), R⁸, R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R⁸ to form a C₁-C₆ alkylene optionallysubstituted by R¹⁰;

each R¹⁰ is independently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl,C₃-C₈ cycloalkyl, 3-12-membered heterocyclyl, 5-10-membered heteroaryl,C₆-C₁₄ aryl, halogen, —CN, —OR¹¹, —SR¹¹, —NR¹²R¹³, —NO₂, —C═NH(OR¹¹),—C(O)R¹¹, —OC(O)R^(u), —C(O)OR¹¹, —C(O)NR¹²R¹³, —NR¹¹C(O)R¹²,—NR¹¹C(O)OR¹², —NR¹¹C(O)NR¹²R¹³, —S(O)R, —S(O)₂R¹¹, —NR¹¹S(O)R¹²,—NR¹¹S(O)₂R¹², —S(O)NR¹²R¹³, —S(O)₂NR¹²R¹³, or —P(O)(OR¹²) (OR¹³);wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl,3-12-membered heterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl ofR¹⁰ are independently optionally substituted by halogen, —CN, oxo,—OR¹⁴, —SR¹⁴, —NR¹⁴R¹⁵, —C(O)R¹⁴, —C(O)OR¹⁴, —S(O)R¹⁴, —S(O)₂R¹⁴,—P(O)(OR¹⁴)(OR¹⁵), 3-12-membered heterocyclyl, 5-10-membered heteroaryl,C₆-C₁₄ aryl, C₃-C₈ cycloalkyl, or C₁-C₆ alkyl optionally substituted byoxo, —OH or halogen, or is taken together with R⁸ to form a C₁-C₆alkylene;

each R^(10A) is independently oxo or R¹⁰;

R¹¹ is independently hydrogen, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl, 5-6-membered heteroaryl or3-6-membered heterocyclyl, wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl, 5-6-membered heteroaryl and3-6-membered heterocyclyl of R¹¹ are independently optionallysubstituted by halogen, oxo, —CN, —OR¹⁶, —NR¹⁶R¹⁷, —P(O)(OR¹⁶ (OR¹⁷), orC₁-C₆ alkyl optionally substituted by halogen, —OH or oxo;

R¹² and R¹³ are each independently hydrogen, C₁-C₆ alkyl, C₂-C₆ alkenyl,C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl, 5-6-membered heteroaryl or3-6 membered heterocyclyl, wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl, 5-6-membered heteroaryl and 3-6membered heterocyclyl of R¹² and R¹³ are independently optionallysubstituted by halogen, oxo, —CN, —OR¹⁶, —NR¹⁶R¹⁷ or C₁-C₆ alkyloptionally substituted by halogen, —OH or oxo;

-   -   or R¹² and R¹³ are taken together with the atom to which they        attached to form a 3-6 membered heterocyclyl optionally        substituted by halogen, oxo, —OR¹⁶, —NR¹⁶R¹⁷ or C₁-C₆ alkyl        optionally substituted by halogen, oxo or —OH; R¹⁴ and R¹⁵ are        each independently hydrogen, C₁-C₆ alkyl optionally substituted        by halogen or oxo, C₂-C₆ alkenyl optionally substituted by        halogen or oxo, or C₂-C₆ alkynyl optionally substituted by        halogen or oxo;    -   or R¹⁴ and R¹⁵ are taken together with the atom to which they        attached to form a 3-6 membered heterocyclyl optionally        substituted by halogen, oxo or C₁-C₆ alkyl optionally        substituted by halogen or oxo; and

R¹⁶ and R¹⁷ are each independently hydrogen, C₁-C₆ alkyl optionallysubstituted by halogen or oxo, C₂-C₆ alkenyl optionally substituted byhalogen or oxo, or C₂-C₆ alkynyl optionally substituted by halogen oroxo;

-   -   or R¹⁶ and R¹⁷ are taken together with the atom to which they        attached to form a 3-6 membered heterocyclyl optionally        substituted by halogen, oxo or C₁-C₆ alkyl optionally        substituted by oxo or halogen.

In some embodiments, where R⁸ and R⁹ are taken together with thenitrogen atom to which they are attached to form a 3-12-memberedheterocyclyl optionally substituted by R¹⁰ or a 5-10-membered heteroaryloptionally substituted by R¹⁰, and the 5-10-membered heteroaryl is afused ring heteroaryl comprising an aryl moiety fused to a heterocyclecontaining the nitrogen atom to which R⁸ and R⁹ are attached, the arylmoiety is not adjacent to the nitrogen atom to which R⁸ and R⁹ areattached. For example, in some embodiments, the 5-10-membered heteroarylformed by R⁸ and R⁹ taken together with the nitrogen atom to which theyare attached is other than indolin-1-yl and3,4-dihydroquinolin-1(2H)-yl.

In some embodiments, the compound is other than a compound in Table 1Xand salts thereof. In some embodiments, the compound herein, such as acompound of formula (A-I) or (I), is other than a compound selected fromone or more of Compound Nos. 1x-83x in Table 1X. In some embodiments,the compounds of the disclosure, and methods of using the compoundsdetailed herein, encompass any of the compounds of formula (A-I) or (I),including one or more of Compound Nos. 1x-83x listed in Table 1X andsalts thereof.

TABLE 1X Compound No. Structure Chemical Name ¹  1x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(pyrrolidin-1- yl)ethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[2-(1-pyrrolidinyl)ethyl]-  2x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(2- morpholinoethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[2-(4-morpholinyl)ethyl]-  3x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(2- (pyrrolidin-1-yl)ethyl)piperidine-4-carboxamide; 4-Piperidinecarboxamide, 1-[2-(4-chlorophenyl)-3,4-dimethyl- 2H-pyrazolo[3,4-d]pyridazin-7-yl]-N-[2-(1-pyrrolidinyl)ethyl]-  4x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(3-morpholinopropyl)piperidine-4- carboxamide; 4-Piperidinecarboxamide,1-(3,4- dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-[3-(4-morpholinyl)propyl]-  5x

N-(2-(diethylamino)ethyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;N-(2-Diethylaminoethyl)-1-(3,4- dimethyl-2-phenylpyrazolo[3,4-d]pyridazin-7-yl)piperidine-4- carboxamide  6x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-(dimethylamino)ethyl)piperidine- 4-carboxamide;N-(2-Dimethylaminoethyl)-1- (3,4-dimethyl-2-phenylpyrazolo[3,4-d]pyridazin- 7-yl)piperidine-4-carboxamide  7x

N-(3-(diethylamino)propyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;N-(3-Diethylaminopropyl)-1- (3,4-dimethyl-2-phenylpyrazolo[3,4-d]pyridazin- 7-yl)piperidine-4-carboxamide  8x

N-(2-(diethylamino)ethyl)-1-(2- (4-methoxyphenyl)-3,4-dimethyl-2H-pyrazolo[3,4- d]pyridazin-7-yl)piperidine-4- carboxamide;4-Piperidinecarboxamide, N-[2- (diethylamino)ethyl]-1-[2-(4-methoxyphenyl)-3,4-dimethyl- 2H-pyrazolo[3,4-d]pyridazin-7- yl]-  9x

N-(3-(diethylamino)propyl)-1- (2-(4-methoxyphenyl)-3,4-dimethyl-2H-pyrazolo[3,4- d]pyridazin-7-yl)piperidine-4- carboxamide;4-Piperidinecarboxamide, N-[3- (diethylamino)propyl]-1-[2-(4-methoxyphenyl)-3,4-dimethyl- 2H-pyrazolo[3,4-d]pyridazin-7- yl]- 10x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(2- (dimethylamino)ethyl)piperidine- 4-carboxamide;4-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[2-(dimethylamino)ethyl]- 11x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(4-methylpiperazin-1- yl)ethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[2-(4-methyl-1- piperazinyl)ethyl]-12x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(2-methylpiperidin-1- yl)ethyl)piperidine-4- carboxamide;1-[3,4-Dimethyl-2-(4- methylphenyl)pyrazolo[3,4-d]pyridazin-7-yl]-N-[2-(2- methylpiperidin-1- yl)ethyl]piperidine-4-carboxamide 13x

N-(2-(butyl(ethyl)amino)ethyl)- 1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;4-Piperidinecarboxamide, N-[2- (butylethylamino)ethyl]-1-[3,4-dimethyl-2-(4-methylphenyl)- 2H-pyrazolo[3,4-d]pyridazin-7- yl]- 14x

N-(2-(azepan-1-yl)ethyl)-1-(3,4- dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;4-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[2-(hexahydro-1H-azepin-1-yl)ethyl]- 15x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(pyrrolidin-1- yl)propyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[3-(1-pyrrolidinyl)propyl]- 16x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-piperidin-1- yl)propyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[3-(1-piperidinyl)propyl]- 17x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-morpholinoethyl)piperidine-4- carboxamide; 4-Piperidinecarboxamide,1-[3,4- dimethyl-2-(4-methylphenyl)- 2H-pyrazolo[3,4-d]pyridazin-7-yl]-N-[2-(4-morpholinyl)ethyl]- 18x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-((1-ethylpyrrolidin-2- yl)methyl)piperidine-4- carboxamide;1-[3,4-Dimethyl-2-(4- methylphenyl)pyrazolo[3,4-d]pyridazin-7-yl]-N-[(1- ethylpyrrolidin-2- yl)methyl]piperidine-4-carboxamide 19x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(3-morpholinopropyl)piperidine-4- carboxamide; 4-Piperidinecarboxamide,1-[3,4- dimethyl-2-(4-methylphenyl)- 2H-pyrazolo[3,4-d]pyridazin-7-yl]-N-[3-(4-morpholinyl)propyl]- 20x

N-(2-(diethylamino)ethyl)-1- (3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;4-Piperidinecarboxamide, N-[2- (diethylamino)ethyl]-1-[3,4-dimethyl-2-(4-methylphenyl)- 2H-pyrazolo[3,4-d]pyridazin-7- yl]- 21x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-(dimethylamino)ethyl)piperidine- 4-carboxamide; 4-Piperidinecarboxamide,N-[2- (dimethylamino)ethyl]-1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]- 22x

N-(3-(diethylamino)propyl)-1- (3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;4-Piperidinecarboxamide, N-[3- (diethylamino)propyl]-1-[3,4-dimethyl-2-(4-methylphenyl)- 2H-pyrazolo[3,4-d]pyridazin-7- yl]- 23x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(4-ethylpiperazin-1- yl)ethyl)piperidine-4- carboxamide;1-(3,4-Dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-[2-(4-ethylpiperazin-1- yl)ethyl]piperidine-4- carboxamide 24x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(2-methylpiperidin-1- yl)ethyl)piperidine-4- carboxamide;1-(3,4-Dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-[2-(2-methylpiperidin-1- yl)ethyl]piperidine-4- carboxamide 25x

N-(2-(butyl(ethyl)amino)ethyl)- 1-(3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;N-[2-(Butyl-ethylamino)ethyl]- 1-(3,4-dimethyl-2-phenylpyrazolo[3,4-d]pyridazin- 7-yl)piperidine-4-carboxamide 26x

N-(2-(azepan-1-yl)ethyl)-1-(3,4- dimethyl-2-phenyl-2H-pyraozlo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[2-(hexahydro-1H-azepin-1- yl)ethyl]-27x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(pyrrolidin-1- yl)propyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[3-(1-pyrrolidinyl)propyl]- 28x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(2-methylpiperidin-1- yl)propyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[3-(2-methyl-1- piperidinyl)propyl]-29x

N-(3-(azepan-1-yl)propyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[3-(hexahydro-1H-azepin-1- yl)propyl]-30x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-piperidin-1- yl)propyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[3-(1-piperidinyl)propyl]- 31x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(4-methylpiperazin-1- yl)propyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[3-(4-methyl-1- piperazinyl)propyl)]-32x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-morpholinoethyl)piperidine-4- carboxamide; 4-Piperidinecarboxamide,1-(3,4- dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-[2-(4-morpholinyl)ethyl]- 33x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-((1-ethylpyrrolidin-2- yl)methyl)piperidine-4- carboxamide;1-(3,4-Dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-[(1-ethylpyrrolidin-2- yl)methyl]piperidine-4- carboxamide 34x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(4-methylpiperazin-1- yl)ethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[2-(4-methyl-1- piperazinyl)ethyl]-35x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(4-methylpiperazin-1- yl)ethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[2-(4-methyl-1- piperazinyl)ethyl]-36x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3- (pyrrolidin-1- yl)propyl)piperidine-3-carboxamide; 3-Piperidinecarboxamide, 1-[2-(4-chlorophenyl)-3,4-dimethyl- 2H-pyrazolo[3,4-d]pyridazin-7-yl]-N-[3-(1-pyrrolidinyl)propyl]- 37x

(1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4- yl)(4-methylpiperazin-1- yl)methanone;Methanone, [1-[2-(4- chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl]- 4-piperidinyl](4-methyl-1- piperazinyl)-38x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(pyrrolidin-1- yl)ethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[2-(1-pyrrolidinyl)ethyl]- 39x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(pyrrolidin-1- yl)propyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[3-(1-pyrrolidinyl)propyl]- 40x

N-(3-(azepan-1-yl)propyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide;3-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[3-(hexahydro-1H-azepin-1- yl)propyl]-41x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3- (diethylamino)propyl)piperidine- 3-carboxamide;3-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[3-(diethylamino)propyl]- 42x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(pyrrolidin-1- yl)ethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[2-(1-pyrrolidinyl)ethyl]- 43x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(2- (pyrrolidin-1-yl)ethyl)piperidine-3-carboxamide; 3-Piperidinecarboxamide, 1-[2-(4-chlorophenyl)-3,4-dimethyl- 2H-pyrazolo[3,4-d]pyridazin-7-yl]-N-[2-(1-pyrrolidinyl)ethyl]- 44x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-morpholinoethyl)piperidine-3- carboxamide; 3-Piperidinecarboxamide,1-(3,4- dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-[2-(4-morpholinyl)ethyl]- 45x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-(dimethylamino)ethyl)piperidine- 3-carboxamide; 3-Piperidinecarboxamide,N-[2- (dimethylamino)ethyl]-1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]- 46x

(1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4- yl)(4-ethylpiperazin-1- yl)methanone;Methanone, [1-[2-(4- chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl]- 4-piperidinyl](4-ethyl-1- piperazinyl)-47x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-3-yl)(4- ethylpiperazin-1-yl)methanone; Methanone,[1-(3,4-dimethyl-2- phenyl-2H-pyrazolo[3,4- d]pyridazin-7-yl)-3-piperidinyl](4-ethyl-1- piperazinyl)- 48x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(2- morpholinoethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[2-(4-morpholinyl)ethyl]- 49x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(3-morpholinopropyl)piperidine-3- carboxamide; 3-Piperidinecarboxamide,1-(3,4- dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-[3-(4-morpholinyl)propyl]- 50x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(2- (diethylamino)ethyl)piperidine- 3-carboxamide;3-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-[2-(diethylamino)ethyl]- 51x

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- ethylpiperazin-1-yl)methanone; Methanone,[1-[3,4-dimethyl-2- (4-methylphenyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl]-4-piperidinyl](4-ethyl-1- piperazinyl)- 52x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-morpholinoethyl)piperidine-3- carboxamide; 3-Piperidinecarboxamide,1-[3,4- dimethyl-2-(4-methylphenyl)- 2H-pyrazolo[3,4-d]pyridazin-7-yl]-N-[2-(4-morpholinyl)ethyl]- 53x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(4-methylpiperazin-1- yl)propyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[3-(4-methyl-1- piperazinyl)propyl]-54x

N-(2-(dimethylamino)ethyl)-1- (2-(4-methoxyphenyl)-3,4-dimethyl-2H-pyrazolo[3,4- d]pyridazin-7-yl)piperidine-3- carboxamide;3-Piperidinecarboxamide, N-[2- (dimethylamino)ethyl]-1-[2-(4-methoxyphenyl)-3,4-dimethyl- 2H-pyrazolo[3,4-d]pyridazin-7- yl]- 55x

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- methylpiperazin-1- yl)methanone; Methanone,[1-[3,4-dimethyl-2- (4-methylphenyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl]-4-piperidinyl](4-methyl-1- piperazinyl)- 56x

N-(2-(diethylamino)ethyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide;N-(2-(diethylamino)ethyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide 57x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-3-yl)(4- methylpiperazin-1- yl)methanone;(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-3-yl)(4- methylpiperazin-1-yl)methanone 58x

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- propylpiperazin-1-yl)methanone;(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- propylpiperazin-1-yl)methanone 59x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- methylpiperazin-1- yl)methanone;(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- methylpiperazin-1-yl)methanone 60x

N-(3-(diethylamino)propyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide;N-(3-(diethylamino)propyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide 61x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- ethylpiperazin-1-yl)methanone;(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- ethylpiperazin-1-yl)methanone 62x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(4-ethylpiperazin-1- yl)ethyl)piperidine-3- carboxamide;1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(4-ethylpiperazin-1- yl)ethyl)piperidine-3- carboxamide 63x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-3-yl)(4- propylpiperazin-1-yl)methanone;(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-3-yl)(4- propylpiperazin-1-yl)methanone 64x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- propylpiperazin-1-yl)methanone;(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- propylpiperazin-1-yl)methanone 65x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-(dimethylamino)ethyl)piperidine- 3-carboxamide;1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-(dimethylamino)ethyl)piperidine- 3-carboxamide 66x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-3- ylmethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-(3-pyridinylmethyl)- 67x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-2- ylmethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-pyridinylmethyl)- 68x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-3- ylmethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-(3-pyridinylmethyl)- 69x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-3- ylmethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-(3-pyridinylmethyl)- 70x

1-(2-(4-methoxyphenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-2- ylmethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-[2- (4-methoxyphenyl)-3,4-dimethyl-2H-pyrazolo[3,4- d]pyridazin-7-yl]-N-(2- pyridinylmethyl)- 71x

1-(2-(4-methoxyphenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-2- ylmethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[2- (4-methoxyphenyl)-3,4-dimethyl-2H-pyrazolo[3,4- d]pyridazin-7-yl]-N-(2- pyridinylmethyl)- 72x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-3- ylmethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-(3-pyridinylmethyl)- 73x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-3- ylmethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-(3-pyridinylmethyl)- 74x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-2- ylmethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-(2-pyridinylmethyl)- 75x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-3- ylmethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-(3-pyridinylmethyl)- 76x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-2- ylmethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-(2-pyridinylmethyl)- 77x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-2- ylmethyl)piperidine-3- carboxamide;3-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-(2-pyridinylmethyl)- 78x

1-(2-(4-methoxyphenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-3- ylmethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[2- (4-methoxyphenyl)-3,4-dimethyl-2H-pyrazolo[3,4- d]pyridazin-7-yl]-N-(3- pyridinylmethyl)- 79x

1-(2-(4-chlorophenyl)-3,4- dimethyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-2- ylmethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[2- (4-chlorophenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-(2-pyridinylmethyl)- 80x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(pyridin-2- ylmethyl)piperidine-4- carboxamide;4-Piperidinecarboxamide, 1-[3,4- dimethyl-2-(4-methylphenyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl]-N-(2-pyridinylmethyl)- 81x

N-(2-(1H-indol-3-yl)ethyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide;3-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[2-(1H-indol-3-yl)ethyl]- 82x

N-(2-(1H-indol-3-yl)ethyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide;4-Piperidinecarboxamide, 1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)- N-[2-(1H-indol-3-yl)ethyl]- 83x

N-(5-chloropyridin-2-yl)-1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide;3-Piperidinecarboxamide, N-(5- chloro-2-pyridinyl)-1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)- ¹ Chemical namesare either index names (IN) or chemical names (CN) for the compound asin CAS Registry ® database, and generated using the ChemBioDraw ® Ultraversion 14.0.0.117 or 16.0.0.82 (68) software.

In one embodiment of the compound of the formula (I), U is a bond (ringA is directly attached to the ring nitrogen of ring B), the compoundhaving the formula (I⁰):

or a salt or solvate thereof, wherein A¹, A², A³, A⁴, A⁵, R¹, R³, R⁶,R⁷, R⁸, R⁹, V, W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments of the compound of formula (A-I), (I) or (I⁰), or asalt or solvate thereof, ring A contains 2 to 4 ring nitrogen atoms. Insome embodiments, at least two of A¹, A², A³, A⁴ and A⁵ are N (orNR^(2a) for A², or NR^(3a) for A³). In some embodiments, at least threeof A¹, A², A³, A⁴ and A⁵ are N (or NR^(2a) for A², or NR^(3a) for A³).In some embodiments, two of A¹, A², A³, A⁴ and A⁵ are N (or NR^(2a) forA², or NR^(3a) for A³). In some embodiments, three of A¹, A², A³, A⁴ andA⁵ are N (or NR^(2a) for A², or NR^(3a) for A³). In some embodiments,four of A¹, A², A³, A⁴ and A⁵ are N (or NR^(2a) for A², or NR^(3a) forA³).

In some embodiments, A¹ is N, A² is CR² and A³ is N. In some of theseembodiments, R² is hydrogen. In some of these embodiments, R² is C₁-C₆alkyl optionally substituted by R^(10A). In some of these embodiments,R² is C₁-C₆ alkyl (e.g., methyl). In some of these embodiments, R² isC₆-C₁₄ aryl optionally substituted by R^(10A). In some of theseembodiments, R² is C₆-C₁₄ aryl (e.g., phenyl).

In some embodiments, A¹ is N, A² is N and A³ is CR³⁰. In some of theseembodiments, R³⁰ is hydrogen. In some of these embodiments, R³⁰ is C₁-C₆alkyl optionally substituted by R^(10A). In some of these embodiments,R³⁰ is C₁-C₆ alkyl (e.g., methyl).

In some embodiments, A¹ is C, A² is CR² and A³ is NH. In some of theseembodiments, R² is hydrogen. In some of these embodiments, R² is C₁-C₆alkyl optionally substituted by R^(10A). In some of these embodiments,R² is C₁-C₆ alkyl (e.g., methyl).

In some embodiments, A¹ is C, A² is NR^(2a) and A³ is N. In some ofthese embodiments, R^(2a) is hydrogen. In some of these embodiments,R^(2a) is C₁-C₆ alkyl optionally substituted by R^(10A). In some ofthese embodiments, R^(2a) is C₁-C₆ alkyl (e.g., methyl).

In some embodiments, A⁴ is CR⁴ and A⁵ is CR⁵. In some embodiments, A⁴ isCR⁴ and A⁵ is N. In some embodiments, A⁴ is N and A⁵ is CR⁵. In someembodiments, A⁴ is N and A⁵ is N. In some of these embodiments, R⁴ ishydrogen. In some of these embodiments, R⁵ is hydrogen.

In some embodiments, A¹ is C, A² is CR², A³ is NR^(3a), A⁴ is N, and A⁵is N. In some of these embodiments, R² is hydrogen. In some of theseembodiments, R^(3a) is hydrogen.

In some embodiments, A¹ is N, A² is CR², A³ is N, A⁴ is N, and A⁵ isCR⁵. In some of these embodiments, R² is hydrogen. In some of theseembodiments, R⁵ is hydrogen.

In some embodiments, A¹ is N, A² is CR², A³ is N, A⁴ is CR⁴, and A⁵ isCR⁵. In some of these embodiments, R² is hydrogen. In some of theseembodiments, R⁴ is hydrogen. In some of these embodiments, R⁵ ishydrogen.

In some embodiments, A¹ is C, A² is NR², A³ is N, A⁴ is CR⁴, and A⁵ isCR⁵. In some of these embodiments, R² is C₁-C₆ alkyl (e.g., methyl). Insome of these embodiments, R⁴ is hydrogen. In some of these embodiments,R⁵ is hydrogen.

It is intended and understood that each and every variation of A¹, A²and A³, described herein, may be combined with each and every variationof A⁴ and A⁵ described herein, the same as if each and every combinationis individually and specifically described. For example, in someembodiments, A¹ is N, A² is CR², A³ is N, A⁴ is CR⁴, and A⁵ is CR⁵. Insome embodiments, A is N, A² is CR², A³ is NH, A⁴ is N, and A⁵ is CR⁵.In some embodiments, A¹ is C, A² is NR^(2a), A³ is N, A⁴ is CR⁴, and A⁵is CR⁵. In some embodiments, A is N, A² is CR², A³ is N, A⁴ is N, and A⁵is CR⁵. In some embodiments, A¹ is N, A² is CR², A³ is N, A⁴ is N, andA⁵ is N. In some of these embodiments, R² is hydrogen. In some of theseembodiments, R^(2a) is methyl. In some of these embodiments, R⁴ ishydrogen. In some of these embodiments, R⁵ is hydrogen.

In some embodiments, the compound of the formula (I) is apyrazolo[3,4-d]pyridazine compound having the formula (Ia):

or a salt or solvate thereof, wherein R¹, R², R³, R⁶, R⁷, R⁸, R⁹, U, V,W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (I), where ring A ispyrazolo[3,4-d]pyridazine and is directly attached to the ring nitrogenof ring B, has the formula (I⁰a):

or a salt or solvate thereof, wherein R¹, R², R³, R⁶, R⁷, R⁸, R⁹, V, W,X, Y, i, j, and n are as defined for formula (I) or (I⁰).

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰) or(I⁰a), or a salt or solvate thereof, ring B is a 3- to 7-memberedheterocycle containing one ring nitrogen atom. In some embodiments, ringB is a 4- to 6-membered heterocycle containing one ring nitrogen atom.In some embodiments, ring B is a 5- or 6-membered heterocycle containingone ring nitrogen atom. In some embodiments, ring B is a pyrrolidinering. In some embodiments, ring B is a piperidine ring.

In some embodiments, i is 2 and j is 1 or 2 (ring B is 1-piperdin-4-ylor 1-azepan-4-yl). In some embodiments, i is 1 and j is 2 (ring B is1-piperdin-3-yl). In some embodiments, i is 1 and j is 1 (ring B is1-pyrrolidin-3-yl). In some embodiments, i is 1 and j is 0 (ring B is1-azetidin-3-yl). In some embodiments, i is 0 and j is 0 (ring B is1-aziridin-2-yl). In some preferred embodiments, i is 2 and j is 1 (ringB is 1-piperdin-4-yl).

It is intended and understood that each and every variation of ring A(e.g., A¹, A², A³, A⁴ and A⁵) described herein, may be combined witheach and every variation of ring B (e.g., i and j) described herein, thesame as if each and every combination is individually and specificallydescribed. For example, in some embodiments, A¹ is N, A² is CR², A³ isN, A⁴ is N, A⁵ is N; i is 2 and j is 1, or i is 1 and j is 2. In someembodiments, A¹ is N, A² is CR², A³ is N, A⁴ is N, A⁵ is N, i is 2 and jis 1.

In some embodiments, the compound of formula (I⁰a) is of the formula(I⁰a-1):

or a salt or solvate thereof, wherein R¹, R², R³, R⁶, R⁷, R⁸, R⁹, V, W,X, Y, and n are as defined for formula (I).

In some embodiments, the compound of formula (I⁰a-1) is of the formula(I⁰a-2):

or a salt or solvate thereof, wherein R¹, R², R³, R⁶, R⁷, R⁸, R⁹, W, X,Y, and n are as defined for formula (I).

It is intended and understood that each and every variation of formula(I⁰) described herein applies to each and every variation of formula(I⁰a), (I⁰a-1), and (I⁰a-2) the same as if each and every variation isindividually and specifically described. Similarly, it is intended andunderstood that each and every variation of formula (I⁰a) describedherein applies to each and every variation of formula (I⁰a-1) and(I⁰a-2) the same as if each and every variation is individually andspecifically described.

In some embodiments, the compound of the formula (I) is of the formula(II):

or a salt or solvate thereof, wherein A¹, A², A³, A⁴, A⁵, R¹, R³, R⁶,R⁷, R⁸, R⁹, U, V, W, X, Y, and n are as defined for formula (I).

In some embodiments, the compound of the formula (II) is apyrazolo[3,4-d]pyridazine compound having the formula (IIa):

or a salt or solvate thereof, wherein R¹, R², R³, R⁶, R⁷, R⁸, R⁹, U, V,W, X, Y, and n are as defined for formula (I) or (II), provided that thecompound is other than any applicable compound in Table 1X (e.g.,Compound Nos. 1x-33x, 37x, 46x, 51x, 55x, 58x, 59x, 61x, 64x, 66x,71x-74x, 78x-80x, or 82x in Table 1X) and salts thereof.

In some embodiments, the compound of formula (IIa) is of the formula(IIa-1):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁷, R⁸, R⁹, U, V, W,X, Y, and n are as defined for formula (I) or any embodiment orvariation thereof, provided that the compound is other than anyapplicable compound in Table 1X (e.g., Compound Nos. 11x-22x, 51x, 55x,58x, 73x, or 80x in Table 1X) and salts thereof.

In some embodiments, the compound of formula (IIa-1) is of the formula(IIa-1a):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁷, R⁸, R⁹, U, V, andn are as defined for formula (I) or any embodiment or variation thereof,k is 1, 2, 3, 4, or 5, provided that the compound is other than anyapplicable compound in Table 1X (e.g., Compound Nos. 11x-17x or 19x-22xin Table 1X) and salts thereof. In some embodiments, k is 1 or 2. Insome embodiments, R⁷ is hydrogen. In some embodiments, R⁸ and R⁹ areeach independently hydrogen or C₁-C₆ alkyl optionally substituted byR¹⁰. In some embodiments, R⁸ is methyl and R⁹ is methyl optionallysubstituted by C₆-C₁₄ aryl. In some embodiments, R⁸ and R⁹ are eachmethyl. In some embodiments, R⁸ is methyl and R⁹ is benzyl.

In some embodiments, the compound of formula (IIa-1a) is of the formula(IIa-1a-1):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁷, U, V, and n are asdefined for formula (I) or any embodiment or variation thereof, R⁸ ishydrogen or methyl optionally substituted by C₆-C₁₄ aryl, k is 1, 2, 3,4, or 5, provided that the compound is other than Compound No. 21x inTable IX and salts thereof. In one embodiment, k is 1 or 2. In someembodiments, R⁷ is hydrogen. In some embodiments, R⁸ is methyloptionally substituted by C₆-C₁₄ aryl. In some embodiments, R⁸ ismethyl. In some embodiments, R⁸ is benzyl.

In some embodiments, the compound of formula (IIa-1a) is of the formula(IIa-1a-2):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁸, R⁹, V, and n areas defined for formula (I) or any embodiment or variation thereof, k is1, 2, 3, 4, or 5, provided that the compound is other than anyapplicable compound in Table IX (e.g., Compound Nos. 11x-17x or 19x-22xin Table IX) and salts thereof. In some embodiments, k is 1 or 2. Insome embodiments, n is 0. In some embodiments, n is 1 or 2, and each R⁶is independently C₁-C₆ alkyl optionally substituted by R^(10A). In someembodiments, n is 1 and R⁶ is C₁-C₆ alkyl (e.g., methyl). In someembodiments, R² and R³ are each hydrogen. In some embodiments, R² and R³are each methyl.

In some embodiments, the compound of formula (IIa-1a-1) is of theformula (IIa-1a-3):

or a salt or solvate thereof, wherein R², R³, R⁶, V, and n are asdefined for formula (I) or any embodiment or variation thereof, R⁸ ishydrogen or methyl optionally substituted by C₆-C₁₄ aryl, k is 1, 2, 3,4, or 5, provided that the compound is other than Compound No. 21x inTable 1X and salts thereof. In some embodiments, k is 1 or 2. In someembodiments, n is 0 or 1. In some embodiments, R² and R³ are eachhydrogen. In some embodiments, R² and R³ are each methyl. In someembodiments, R⁸ is methyl optionally substituted by C₆-C₁₄ aryl. In someembodiments, R⁸ is methyl. In some embodiments, R⁸ is benzyl.

In a preferred embodiment, the compound of formula (IIa-1a-3) isCompound No. 1:

In a preferred embodiment, the compound of formula (IIa-1a-3) isCompound No. 9:

In a preferred embodiment, the compound of formula (IIa-1a-3) isCompound No. 20:

In a preferred embodiment, the compound of formula (IIa-1a-3) isCompound No. 22:

In a preferred embodiment, the compound of formula (IIa-1a-3) isCompound No. 29:

In a preferred embodiment, the compound of formula (IIa-1a-3) isCompound No. 46:

In a preferred embodiment, the compound of formula (IIa-1a-3) isCompound No. 61:

In some embodiments, the compound of formula (IIa-1) is of the formula(IIa-1b):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁸, R⁹, U, V, and nare as defined for formula (I) or any embodiment or variation thereof.In one embodiment, R² and R³ are each hydrogen. In another embodiment,R² and R³ are each methyl. In some embodiments, U is a bond. In someembodiments, V is bond. In some embodiments, n is 0. In someembodiments, R⁸ and R⁹ are independently C₁-C₆ alkyl optionallysubstituted by R¹⁰. In some embodiments, R⁸ and R⁹ are each methyl.

In some embodiments, the compound of formula (IIa-1b) is of the formula(IIa-1b-1):

or a salt or solvate thereof, wherein R², R³, R⁶, U, V, and n are asdefined for formula (I) or any embodiment or variation thereof. In someembodiments, R² and R³ are each hydrogen. In some embodiments, R² and R³are each methyl. In some embodiments, U is a bond. In some embodiments,V is bond. In some embodiments, n is 0.

In some embodiments, the compound of formula (IIa-1b) is of the formula(IIa-1b-2):

or a salt or solvate thereof, wherein R², R³, R⁸, and R⁹ are as definedfor formula (I), or any embodiment or variation thereof. In someembodiments, R² and R³ are each hydrogen. In some embodiments, R² and R³are each methyl. In some embodiments, R⁸ and R⁹ are independently C₁-C₆alkyl optionally substituted by R¹⁰. In some embodiments, R⁸ and R⁹ areeach methyl.

In some embodiments, the compound of formula (IIa-1b) is of the formula(IIa-1b-3):

or a salt or solvate thereof, wherein R² and R³ are as defined forformula (I) or any embodiment or variation thereof. In one embodiment,R² and R³ are each hydrogen. In another embodiment, R² and R³ are eachmethyl.

In a preferred embodiment, the compound of formula (IIa-1b-3) isCompound No. 45:

In a preferred embodiment, the compound of formula (IIa-1b-3) isCompound No. 60:

In some embodiments, the compound of formula (IIa-1) is of the formula(IIa-1c):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁸, R⁹, U, V, and nare as defined for formula (I) or any embodiment or variation thereof.In some embodiments, R² and R³ are each hydrogen. In some embodiments,R² and R³ are each methyl. In some embodiments, U is a bond. In someembodiments, V is bond. In some embodiments, n is 0. In someembodiments, R⁸ and R⁹ are independently C₁-C₆ alkyl optionallysubstituted by R¹⁰. In some embodiments, R⁸ and R⁹ are each ethyl. Insome embodiments, R⁸ and R⁹ are taken together with the nitrogen atom towhich they are attached to form a 3- to 12-membered heterocyclyloptionally substituted by R¹⁰. In some embodiments, R⁸ and R⁹ are takentogether with the nitrogen atom to which they are attached to formazetanyl.

In some embodiments, the compound of formula (IIa-1c) is of the formula(IIa-1c-1):

or a salt or solvate thereof, wherein R² and R³ are as defined forformula (I) or any embodiment or variation thereof. In some embodiments,R² and R³ are each hydrogen. In some embodiments, R² and R³ are eachmethyl. In some embodiments, R⁸ and R⁹ are independently C₁-C₆ alkyloptionally substituted by R¹⁰. In some embodiments, R⁸ and R⁹ are eachethyl. In some embodiments, R⁸ and R⁹ are taken together with thenitrogen atom to which they are attached to form a 3- to 12-memberedheterocyclyl optionally substituted by R¹⁰. In some embodiments, R⁸ andR⁹ are taken together with the nitrogen atom to which they are attachedto form azetanyl.

In a preferred embodiment, the compound of formula (IIa-1c-1) isCompound No. 43:

In a preferred embodiment, the compound of formula (IIa-1c-1) isCompound No. 59:

In a preferred embodiment, the compound of formula (IIa-1c-1) isCompound No. 65:

In some embodiments, the compound of formula (IIa-1) is of the formula(IIa-1d):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁸, R⁹, U, V, and nare as defined for formula (I) or any embodiment or variation thereof.In some embodiments, R² and R³ are each hydrogen. In some embodiments,R² and R³ are each methyl. In some embodiments, R⁷ is hydrogen. In someembodiments, U is a bond. In some embodiments, V is bond. In someembodiments, n is 0. In some embodiments, R⁹ is C₁-C₆ alkyl optionallysubstituted by R¹⁰. In some embodiments, R⁹ is methyl.

In some embodiments, the compound of formula (IIa-1d) is of the formula(IIa-1d-1):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁷, U, V, and n are asdefined for formula (I) or any embodiment or variation thereof. In someembodiments, R² and R³ are each hydrogen. In some embodiments, R² and R³are each methyl. In some embodiments, R⁷ is hydrogen. In someembodiments, U is a bond. In some embodiments, V is bond. In someembodiments, n is 0.

In some embodiments, the compound of formula (IIa-1d) is of the formula(IIa-1d-2):

or a salt or solvate thereof, wherein R², R³, and R⁹ are as defined forformula (I) or any embodiment or variation thereof. In some embodiments,R² and R³ are each hydrogen. In some embodiments, R² and R³ are eachmethyl. In some embodiments, R⁹ is C₁-C₆ alkyl optionally substituted byR¹⁰. In some embodiments, R⁹ is methyl.

In some embodiments, the compound of formula (IIa-1d) is of the formula(IIa-1d-3):

or a salt or solvate thereof, wherein R² and R are as defined forformula (I) or any embodiment or variation thereof. In some embodiments,R² and R³ are each hydrogen. In some embodiments, R² and R³ are eachmethyl.

In a preferred embodiment, the compound of formula (IIa-1d-3) isCompound No. 62:

In some embodiments, the compound of formula (IIa-1) is of the formula(IIa-1e):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁹, U, V, and n are asdefined for formula (I) or any embodiment or variation thereof. In someembodiments, R² and R³ are each hydrogen. In some embodiments, R² and R³are each methyl. In some embodiments, U is a bond. In some embodiments,V is bond. In some embodiments, n is 0. In some embodiments, R⁹ is C₁-C₆alkyl optionally substituted by R¹⁰. In some embodiments, R⁹ is methyl.

In some embodiments, the compound of formula (IIa-1e) is of the formula(IIa-1e-1):

or a salt or solvate thereof, wherein R², R³, R⁶, U, V, and n are asdefined for formula (I) or any embodiment or variation thereof. In someembodiments, R² and R³ are each hydrogen. In some embodiments, R² and R³are each methyl. In some embodiments, U is a bond. In some embodiments,V is bond. In some embodiments, n is 0.

In some embodiments, the compound of formula (IIa-1e) is of the formula(IIa-1e-2):

or a salt or solvate thereof, wherein R², R³, and R⁹ are as defined forformula (I) or any embodiment or variation thereof. In some embodiments,R² and R³ are each hydrogen. In some embodiments, R² and R³ are eachmethyl. In some embodiments, R⁹ is C₁-C₆ alkyl optionally substituted byR¹⁰. In some embodiments, R⁹ is methyl.

In some embodiments, the compound of formula (IIa-1e) is of the formula(IIa-1e-3):

or a salt or solvate thereof, wherein R² and R³ are as defined forformula (I) or any embodiment or variation thereof. In some embodiments,R² and R³ are each hydrogen. In some embodiments, R² and R³ are eachmethyl.

In a preferred embodiment, the compound of formula (IIa-1e-3) isCompound No. 75:

In some embodiments, the compound of formula (IIa-1) is of the formula(IIa-1f):

or a salt or solvate thereof, wherein R², R³, R⁶, R⁹, U, V, and n are asdefined for formula (I) or any embodiment or variation thereof. In someembodiments, R⁹ is C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, R⁹ is methyl.

In some embodiments, the compound of formula (IIa-1f) is of the formula(IIa-1f-1):

or a salt or solvate thereof, wherein R², R³, R⁶, U, V, and n are asdefined for formula (I) or any embodiment or variation thereof. In someembodiments, R² and R³ are each hydrogen. In some embodiments, R² and R³are each methyl. In some embodiments, U is a bond. In some embodiments,V is bond. In some embodiments, n is 0.

In some embodiments, the compound of formula (IIa-1f) is of the formula(IIa-1f-2):

or a salt or solvate thereof, wherein R², R³, and R⁹ are as defined forformula (I) or any embodiment or variation thereof. In some embodiments,R² and R³ are each hydrogen. In some embodiments, R² and R³ are eachmethyl. In some embodiments, R⁹ is C₁-C₆ alkyl optionally substituted byR¹⁰. In some embodiments, R⁹ is methyl.

In some embodiments, the compound of formula (IIa-1f) is of the formula(IIa-1f-3):

or a salt or solvate thereof, wherein R² and R³ are as defined forformula (I) or any embodiment or variation thereof. In some embodiments,R² and R³ are each hydrogen. In some embodiments, R² and R³ are eachmethyl.

In a preferred embodiment, the compound of formula (IIa-1f-3) isCompound No. 72:

It is intended and understood that each and every variation of formula(II) described herein applies to each and every variation of formula(IIa), (IIa-1), (IIa-a), (IIa-1a-1), (IIa-a-2), (IIa-1a-3), (IIa-1b),(IIa-1b-1), (IIa-1b-2), (IIa-1b-3), (IIa-1c), (IIa-1c-1), (IIa-d),(IIa-1d-1), (IIa-1d-2), (IIa-1d-3), (IIa-1e), (IIa-1e-1), (IIa-1e-2),(IIa-1e-3), (IIa-1f), (IIa-1f-1), (IIa-1f-2), and (IIa-1f-3) the same asif each and every variation is individually and specifically described.Similarly, it is intended and understood that each and every variationof formula (IIa) described herein applies to each and every variation offormula (IIa-1), (IIa-1a), (IIa-1a-1), (IIa-1a-2), (IIa-1a-3), (IIa-1b),(IIa-1b-1), (IIa-1b-2), (IIa-1b-3), (IIa-1c), (IIa-1c-1), (IIa-d),(IIa-1d-1), (IIa-1d-2), (IIa-1d-3), (IIa-1e), (IIa-1e-1), (IIa-1e-2),(IIa-1e-3), (IIa-1f), (IIa-1f-1), (IIa-1f-2), and (IIa-1f-3) the same asif each and every variation is individually and specifically described.

In some embodiments of the compound of formula (A-I), (I), (Ia), (II),(IIa), or any variation thereof, or a salt or solvate thereof, U is abond (or absent) or an optionally substituted methylene. In someembodiments, U is a bond. In some embodiments, U is methylene optionallysubstituted by R¹⁰. In some embodiments, U is methylene (—CH₂—).

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), or any variation thereof, or a salt or solvatethereof, V is a bond (or absent) or an optionally substituted methyleneor ethylene. In some embodiments, V is a bond. In some embodiments, V isC₁-C₂ alkylene optionally substituted by R¹⁰. In some embodiments, V ismethylene (—CH₂—). In some embodiments, V is ethylene (—CH₂CH₂—). Insome embodiments, U is a bond and V is a bond, methylene (—CH₂—) orethylene (—CH₂CH₂—).

It is intended and understood that each and every variation of ring A(e.g., A¹, A², A³, A⁴ and A⁵) and ring B (e.g., i and j) describedherein, may be combined with each and every variation of linkers U and Vdescribed herein, the same as if each and every combination isindividually and specifically described. For example, in someembodiments, A¹ is N, A² is CR², A³ is N, A⁴ is N, A⁵ is N, i is 2, is1, U is a bond, and V is a bond or ethylene (—CH₂CH₂—). In some of theseembodiments, R² is hydrogen or methyl. In some of these embodiments, Vis a bond.

In some embodiments of the compound of the formula (II), both U and Vare absent, the compound is of the formula (III):

or a salt or solvate thereof, wherein A¹, A², A³, A⁴, A⁵, R¹, R³, R⁶,R⁷, R⁸, R⁹, W, X, Y, and n are as defined for formula (I) or (II).

In some embodiments, the compound of the formula (III) is apyrazolo[3,4-d]pyridazine compound having the formula (IIIa):

or a salt or solvate thereof, wherein R¹, R², R³, R⁶, R⁷, R⁸, R⁹, W, X,Y, and n are as defined for formula (I), (II) or (III).

In some embodiments, the compound of the formula (I) is apyrazolo[3,4-d]pyridazine compound having the formula (IV):

or a salt or solvate thereof, wherein R¹, R³, R³⁰, R⁶, R⁷, R⁸, R⁹, U, V,W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (IV), where ring A ispyrazolo[3,4-d]pyridazin-4-yl and is directly attached to the ringnitrogen of ring B, has the formula (IV-a):

or a salt or solvate thereof, wherein R¹, R³, R³⁰, R⁶, R⁷, R⁸, R⁹, V, W,X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (IV-a) is of theformula (IV-a-1):

or a salt or solvate thereof, wherein R⁶, R⁷, R⁸, R⁹, V, W, X, Y, i, j,and n are as defined for formula (I). In some embodiments, R³ ishalogen. In some embodiments, R³⁰ is C₁-C₆ alkyl. In some embodiments,R³ is halogen and R³⁰ is C₁-C₆ alkyl.

In some embodiments, the compound of formula (IV-a-1) is of the formula(IV-a-2):

or a salt or solvate thereof, wherein R⁶, R⁸, R⁹, V, and n are asdefined for formula (I) or any embodiment or variation thereof, and k is1, 2, 3, 4, or 5. In some embodiments, V is a bond. In some embodiments,V is C₁-C₆ alkylene (e.g., ethylene). In some embodiments, k is 1 or 2.In some embodiments, n is 0. In some embodiments, R⁸ and R⁹ areindependently C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, R⁸ and R⁹ are each methyl.

In one embodiment, the compound of formula (IV-a-2) is Compound No. 48:

It is intended and understood that each and every variation of formula(IV) described herein applies to each and every variation of formula(IV-a), (IV-a-1), and (IV-a-2) the same as if each and every variationis individually and specifically described. Similarly, it is intendedand understood that each and every variation of formula (IV-a) describedherein applies to each and every variation of formula (IV-a-1) and(IV-a-2) the same as if each and every variation is individually andspecifically described.

In some embodiments, the compound of the formula (I) is an indazolecompound having the formula (V):

or a salt or solvate thereof, wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸,R⁹, U, V, W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (V), where ring A is anindazol-7-yl and is directly attached to the ring nitrogen of ring B,has the formula (V-a):

or a salt or solvate thereof, wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸,R⁹, V, W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (V-a) is of the formula(V-a-1):

or a salt or solvate thereof, wherein R⁶, R⁷, R⁸, R⁹, V, W, X, Y, i, j,and n are as defined for formula (I).

In some embodiments, the compound of formula (V-a-1) is of the formula(V-a-2):

or a salt or solvate thereof, wherein R⁶, R⁸, R⁹, V, and n are asdefined for formula (I) or any embodiment or variation thereof, and k is1, 2, 3, 4, or 5. In some embodiments, V is a bond. In some embodiments,V is C₁-C₆ alkylene (e.g., ethylene). In some embodiments, k is 1 or 2.In some embodiments, n is 0. In some embodiments, R⁸ and R⁹ areindependently C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, R⁸ and R⁹ are each methyl.

In one embodiment, the compound of formula (V-a-2) is Compound No. 49:

In one embodiment, the compound of formula (V-a-2) is Compound No. 50:

It is intended and understood that each and every variation of formula(V) described herein applies to each and every variation of formula(V-a), (V-a-1), and (V-a-2) the same as if each and every variation isindividually and specifically described. Similarly, it is intended andunderstood that each and every variation of formula (V-a) describedherein applies to each and every variation of formula (V-a-1) and(V-a-2) the same as if each and every variation is individually andspecifically described.

In some embodiments, the compound of the formula (I) is apyrrolo[2,3-d]pyridazine compound having the formula (VI):

or a salt or solvate thereof, wherein R¹, R², R³, R^(3a), R⁶, R⁷, R⁸,R⁹, U, V, W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (VI), where ring A ispyrrolo[2,3-d]pyridazin-7-yl and is directly attached to the ringnitrogen of ring B, has the formula (VI-a):

or a salt or solvate thereof, wherein R¹, R², R³, R^(3a), R⁶, R⁷, R⁸,R⁹, V, W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (VI-a) is of theformula (VI-a-1):

or a salt or solvate thereof, wherein R⁶, R⁷, R⁸, R⁹, V, W, X, Y, i, j,and n are as defined for formula (I).

In some embodiments, the compound of formula (VI-a-1) is of the formula(VI-a-2):

or a salt or solvate thereof, wherein R⁶, R⁸, R⁹, V, and n are asdefined for formula (I) or any embodiment or variation thereof, and k is1, 2, 3, 4, or 5. In some embodiments, V is a bond. In some embodiments,V is C₁-C₆ alkylene (e.g., ethylene). In some embodiments, k is 1 or 2.In some embodiments, n is 0. In some embodiments, R⁸ and R⁹ areindependently C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, R⁸ and R⁹ are each methyl.

In one embodiment, the compound of formula (VI-a-2) is Compound No. 51:

In one embodiment, the compound of formula (VI-a-2) is Compound No. 52:

It is intended and understood that each and every variation of formula(VI) described herein applies to each and every variation of formula(VI-a), (VI-a-1), and (VI-a-2) the same as if each and every variationis individually and specifically described. Similarly, it is intendedand understood that each and every variation of formula (VI-a) describedherein applies to each and every variation of formula (VI-a-1) and(VI-a-2) the same as if each and every variation is individually andspecifically described.

In some embodiments, the compound of the formula (I) is abenzo[d]imidazole compound having the formula (VII):

or a salt or solvate thereof, wherein R¹, R^(2a), R³, R⁴, R⁵, R⁶, R⁷,R⁸, R⁹, U, V, W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (VII), where ring A isbenzo[d]imidazole-4-yl and is directly attached to the ring nitrogen ofring B, has the formula (VII-a):

or a salt or solvate thereof, wherein R¹, R^(2a), R³, R⁴, R⁵, R⁶, R⁷,R⁸, R⁹, V, W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (VII-a) is of theformula (VII-a-1):

or a salt or solvate thereof, wherein R⁶, R⁷, R⁸, R⁹, V, W, X, Y, i, j,and n are as defined for formula (I).

In some embodiments, the compound of formula (VII-a-1) is of the formula(VII-a-2):

or a salt or solvate thereof, wherein R⁶, R⁸, R⁹, V, and n are asdefined for formula (I) or any embodiment or variation thereof, and k is1, 2, 3, 4, or 5. In some embodiments, V is a bond. In some embodiments,V is C₁-C₆ alkylene (e.g., ethylene). In some embodiments, k is 1 or 2.In some embodiments, n is 0. In some embodiments, R⁸ and R⁹ areindependently C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, R⁸ and R⁹ are each methyl.

In one embodiment, the compound of formula (VII-a-2) is Compound No. 53:

In one embodiment, the compound of formula (VII-a-2) is Compound No. 54:

It is intended and understood that each and every variation of formula(VII) described herein applies to each and every variation of formula(VII-a), (VII-a-1), and (VII-a-2) the same as if each and everyvariation is individually and specifically described. Similarly, it isintended and understood that each and every variation of formula (VII-a)described herein applies to each and every variation of formula(VII-a-1) and (VII-a-2) the same as if each and every variation isindividually and specifically described.

In some embodiments, the compound of the formula (I) is apyrazolo[4,3-c]pyridine compound having the formula (VIII):

or a salt or solvate thereof, wherein R¹, R², R³, R⁵, R⁶, R⁷, R⁸, R⁹, U,V, W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (VIII), where ring A ispyrazolo[4,3-c]pyridine-7-yl and is directly attached to the ringnitrogen of ring B, has the formula (VIII-a):

or a salt or solvate thereof, wherein R¹, R², R³, R⁵, R⁶, R⁷, R⁸, R⁹, V,W, X, Y, i, j, and n are as defined for formula (I).

In some embodiments, the compound of the formula (VIII-a) is of theformula (VIII-a-1):

or a salt or solvate thereof, wherein R⁶, R⁷, R⁸, R⁹, V, W, X, Y, i, j,and n are as defined for formula (I).

In some embodiments, the compound of formula (VIII-a-1) is of theformula (VIII-a-2):

or a salt or solvate thereof, wherein R⁶, R⁸, R⁹, V, and n are asdefined for formula (I) or any embodiment or variation thereof, and k is1, 2, 3, 4, or 5. In some embodiments, V is a bond. In some embodiments,V is C₁-C₆ alkylene (e.g., ethylene). In some embodiments, k is 1 or 2.In some embodiments, n is 0. In some embodiments, R⁸ and R⁹ areindependently C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, R⁸ and R⁹ are each methyl.

In a preferred embodiment, the compound of formula (VIII-a-2) isCompound No. 55:

In one embodiment, the compound of formula (VIII-a-2) is Compound No.56:

It is intended and understood that each and every variation of formula(VIII) described herein applies to each and every variation of formula(VIII-a), (VIII-a-1), and (VIII-a-2) the same as if each and everyvariation is individually and specifically described. Similarly, it isintended and understood that each and every variation of formula(VIII-a) described herein applies to each and every variation of formula(VIII-a-1) and (VIII-a-2) the same as if each and every variation isindividually and specifically described.

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a) or any variation thereof, or asalt or solvate thereof, ring B may be optionally substituted with up to4 additional substituents. In some embodiments, n is 0. In someembodiments, n is 1 or 2, and each R⁶ is independently C₁-C₆ alkyloptionally substituted by R^(10A). In some embodiments, n is 1 and R⁶ isC₁-C₆ alkyl (e.g., methyl).

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a) or any variation thereof, or asalt or solvate thereof, R¹ is C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄aryl, 5-10-membered heteroaryl or 3-12-membered heterocyclyl; each ofwhich may be optionally independently substituted by up to five R^(10A)groups. In some embodiments, R¹ is phenyl optionally substituted byR^(10A). In some embodiments, R¹ is phenyl optionally substituted byC₁-C₆ alkyl or halo (e.g., 4-methylphenyl or 4-chlorophenyl). In someembodiments, R¹ is C₁-C₆ alkyl optionally substituted by R^(10A). Insome embodiments, R¹ is C₁-C₆ alkyl (e.g., 2-propyl). In someembodiments, R¹ is 3-12-membered heterocyclyl optionally substituted byR^(10A). In some embodiments, R¹ is 3-12-membered heterocyclyl (e.g.,tetrahydropyran-4-yl). In some embodiments, R¹ is 5-10-memberedheteroaryl optionally substituted by R^(10A). In some embodiments, R¹ is5-10-membered heteroaryl (e.g., pyridyl, thiophenyl, or oxazolyl).

In some embodiments, R² is C₁-C₆ alkyl optionally substituted byR^(10A). In some embodiments, R² is C₁-C₆ alkyl (e.g., methyl). In someembodiments, R² is hydrogen. In some embodiments, R² is C₆-C₁₄ aryloptionally substituted by R^(10A). In some embodiments, R² is C₆-C₁₄aryl (e.g., phenyl). In some embodiments, R² is halogen (e.g., F, Cl, Bror I). In some embodiments, R² is C₃-C₈ cycloalkyl optionallysubstituted by R^(10A). In some embodiments, R² is 5-10-memberedheteroaryl optionally substituted by R^(10A). In some embodiments, R² is3-12-membered heterocyclyl optionally substituted by R^(10A).

In some embodiments, R³ is C₁-C₆ alkyl optionally substituted byR^(10A). In some embodiments, R³ is C₁-C₆ alkyl (e.g., methyl). In someembodiments, R³ is C₁-C₆ alkyl substituted independently by 1 to 5halogen atoms (e.g., CF₃). In some embodiments, R³ is hydrogen. In someembodiments, R³ is C₆-C₁₄ aryl optionally substituted by R^(10A). Insome embodiments, R³ is C₆-C₁₄ aryl (e.g., phenyl). In some embodiments,R³ is halogen (e.g., F, Cl, Br or I). In some embodiments, R³ is C₃-C₈cycloalkyl optionally substituted by R^(10A). In some embodiments, R³ is5-10-membered heteroaryl optionally substituted by R^(10A). In someembodiments, R³ is 3-12-membered heterocyclyl optionally substituted byR^(10A).

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a) or any variation thereof, or asalt or solvate thereof, R⁷ is hydrogen, C₁-C₆ alkyl, or taken togetherwith R⁸ to form an ethylene optionally substituted by R¹⁰, or takentogether with R^(Y1), R^(X1) or R^(W1), where present, to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R⁷ ishydrogen or C₁-C₆ alkyl. In some embodiments, R⁷ is hydrogen. In someembodiments, R⁷ is C₁-C₆ alkyl. In some embodiments, R⁷ is takentogether with R^(Y1), R^(X1) or R^(W1), where present, to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R⁷ is takentogether with R^(Y1), R^(X1) or R^(W1), where present, to form a C₁-C₄alkylene optionally substituted by R¹⁰. In some embodiments, R⁷ is takentogether with R^(Y1), R^(X1) or R^(W1), where present, to form apropylene, ethylene, or methylene optionally substituted by R¹⁰.

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a) or any variation thereof, or asalt or solvate thereof, R⁸ is hydrogen, C₁-C₆ alkyl optionallysubstituted by R¹⁰, C₆-C₁₄ aryl, 5-10-membered heteroaryl, or takentogether with R⁷ to form an ethylene optionally substituted by R¹⁰, ortaken together with R^(Y1), R^(Y2), R^(X1), R^(X2), or R^(W1), wherepresent, to form a C₁-C₆ alkylene optionally substituted by R¹⁰, ortaken together with R¹⁰, where present, to form a C₁-C₆ alkylene, ortaken together with R⁹ and the nitrogen atom to which they are attachedto form a 3-12-membered heterocyclyl optionally substituted by R¹⁰ or a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(Y1), R^(Y2), R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl (e.g., 4-imidazolyl or2-pyridyl) optionally substituted by R¹⁰, or taken together with R^(X1),R^(X2), R^(Y1), R^(Y2), R⁹ and the atoms to which they are attached toform a 5-10-membered heteroaryl (e.g., 3-pyridyl) optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(X2), R^(Y1), R^(Y2), R⁹ and the atoms to which they are attached toform a 5-10-membered heteroaryl (e.g., 4-pyridyl) optionally substitutedby R¹⁰. In some embodiments, R is hydrogen or C₁-C₆ alkyl optionallysubstituted by R¹⁰. In some embodiments, R⁸ is hydrogen or C₁-C₆ alkyl.In some embodiments, R⁸ is hydrogen. In some embodiments, R⁸ is C₁-C₆alkyl optionally substituted by R¹⁰ (e.g., benzyl). In some embodiments,R⁸ is C₁-C₆ alkyl (e.g., methyl or 2-propyl). In some embodiments, R⁸ istaken together with R^(Y1), R^(Y2), R^(X1), R^(X2), or R^(W1), wherepresent, to form a C₁-C₆ alkylene optionally substituted by R¹⁰. In someembodiments, R⁸ is taken together with R¹⁰, where present, to form aC₁-C₆ alkylene. In some embodiments, R⁸ is C₆-C₁₄ aryl. In someembodiments, R⁸ is phenyl. In some embodiments, when R⁸ is phenyl, R⁹ ishydrogen or C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, R⁸ is 5-10-membered heteroaryl.

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a) or any variation thereof, or asalt or solvate thereof, R⁹ is hydrogen, C₁-C₆ alkyl optionallysubstituted by R¹⁰, or taken together with R⁸ and the nitrogen atom towhich they are attached to form a 3-12-membered heterocyclyl optionallysubstituted by R¹⁰ or a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(Y1), R^(Y2), R⁸ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰, or taken together with R^(X1), R^(X2), R^(Y1),R^(Y2), R⁸ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(W1), R^(W2), where present, R^(X), R^(X2), R^(Y)R^(Y2),R⁸ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰. In some embodiments, R⁹ ishydrogen or C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, R⁹ is hydrogen. In some embodiments, R⁹ is C₁-C₆ alkyloptionally substituted by R¹⁰. In some embodiments, R⁹ is C₁-C₆ alkylsubstituted by phenyl (e.g., benzyl). In some embodiments, R⁹ is C₁-C₆alkyl (e.g., methyl or 2-propyl).

In some embodiments, each R⁸ and R⁹ is independently hydrogen or C₁-C₆alkyl optionally substituted by R¹⁰. In some embodiments, each R⁸ and R⁹is independently C₁-C₆ alkyl optionally substituted by R¹⁰. In someembodiments, each R⁸ and R⁹ is methyl. In some embodiments, R⁸ is methyland R⁹ is benzyl. In some embodiments, R⁸ is hydrogen and R⁹ is methyl,2-propyl or benzyl.

In some embodiments, R⁷ and R⁸ are taken together to form an ethyleneoptionally substituted by R¹⁰. In some embodiments, R⁷ and R⁸ are takentogether to form an ethylene (—CH₂CH₂—).

In some embodiments, R⁸ and R⁹ are taken together with the nitrogen atomto which they are attached to form a 3-12-membered heterocyclyloptionally substituted by R¹⁰ or a 5-10-membered heteroaryl optionallysubstituted by R¹⁰. In some embodiments, R⁸ and R⁹ are taken togetherwith the nitrogen atom to which they are attached to form a3-12-membered heterocyclyl optionally substituted by R¹⁰. In someembodiments, R⁸ and R⁹ are taken together with the nitrogen atom towhich they are attached to form a 3-7-membered heterocyclyl (e.g.,azetidinyl, pyrrolidinyl and morpholinyl) optionally substituted by R¹⁰.In some embodiments, R⁸ and R⁹ are taken together with the nitrogen atomto which they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰. In some embodiments, the 5-10-membered heteroaryl isa monocyclic 5- or 6-membered heteroaryl (e.g., 1-imidazolyl). In someembodiments, the 5-10-membered heteroaryl is a fused ring heteroarylcomprising an aryl moiety fused to a heterocycle containing the nitrogenatom to which R⁸ and R⁹ are attached. In some embodiments, the5-10-membered heteroaryl is a fused ring heteroaryl comprising an arylmoiety fused to a heterocycle containing the nitrogen atom to which R⁸and R⁹ are attached and the aryl moiety is not adjacent to the nitrogenatom to which R⁸ and R⁹ are attached. In some embodiments, R⁸ and R⁹ aretaken together with the nitrogen atom to which they are attached to forma 5-6-membered heterocyclyl (e.g., pyrrolidinyl or piperidinyl) fusedwith an aryl or heteroaryl optionally substituted by R¹⁰. In someembodiments, R⁸ and R⁹ are taken together with the nitrogen atom towhich they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰, wherein the 5-10-membered heteroaryl is other thanindolin-1-yl and 3,4-dihydroquinolin-1(2H)-yl.

In some embodiments, R⁸ is taken together with R^(Y1), R^(Y2), R^(X1),R^(X2), or R^(W1), where present, to form a C₁-C₆ alkylene optionallysubstituted by R¹⁰. In some embodiments, R⁸ is taken together withR^(Y1), R^(Y2), R^(X1), R^(X2), or R^(W1), where present, to form aC₁-C₄ alkylene optionally substituted by R¹⁰. In some embodiments, R⁸ istaken together with R^(Y1), R^(Y2), R^(X1)R^(X2), or R^(W1), wherepresent, to form a methylene (—CH₂—), ethylene (—CH₂CH₂—), or propylene(—CH₂CH₂CH₂—).

In some embodiments, R⁸ is taken together with R¹⁰, where present, toform a C₁-C₆ alkylene. In some embodiments, R⁸ is taken together withR¹⁰, where present, to form a C₁-C₄ alkylene. In some embodiments, R⁸ istaken together with R¹⁰, where present, to form a methylene (—CH₂—),ethylene (—CH₂CH₂—), or propylene (—CH₂CH₂CH₂—).

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a) or any variation thereof, or asalt or solvate thereof, W is a bond or C₁-C₄ alkylene optionallysubstituted by one or both of R^(W1) and R^(W2). R^(W1), where present,is C₁-C₆ alkyl optionally substituted by R^(10A), or taken together withR⁷, R⁸, R^(X1) or R^(Y1) to form a C₁-C₆ alkylene optionally substitutedby R¹⁰, or taken together with R^(W2), R^(X1), R^(X2), R^(Y), R^(Y2),R⁸, R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰. R^(W2), where present, isC₁-C₆ alkyl optionally substituted by R^(10A), or taken together withR^(W1), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰. In some embodiments, W is a bond (or absent). Insome embodiments, W is a bond or C₁-C₄ alkylene. In some embodiments, Wis a C₁-C₄ alkylene. In some embodiments, W is methylene (—CH₂—),ethylene (—CH₂CH₂—), propylene (—CH₂CH₂CH₂—), or butylene(—CH₂(CH₂)₂CH₂—). In some embodiments, W is methylene (—CH₂—). In someembodiments, W is ethylene (—CH₂CH₂—). In some embodiments, W ispropylene (—CH₂CH₂CH₂—).

In some embodiments, W is C₁-C₄ alkylene optionally substituted by oneor both of R^(W1) and R^(W2).

In some embodiments, W is C₁-C₄ alkylene substituted by R^(W1). In someembodiments, W is —CHR^(W1)—. In some embodiments, W is —CH₂—CHR^(W1)—.In some embodiments, W is —CH₂CH₂—CHR^(W1)—. In some of theseembodiments, R^(W1) is C₁-C₆ alkyl optionally substituted by R^(10A). Insome of these embodiments, R^(W1) is C₁-C₆ alkyl (e.g., methyl). In someof these embodiments, R^(W1) is taken together with R⁷, R⁸, R^(X1) orR^(Y1) to form a C₁-C₆ alkylene optionally substituted by R¹⁰.

In some embodiments, W is C₁-C₄ alkylene substituted by R^(W1) andR^(W2), wherein R^(W1) and R^(W2) may be attached to the same ordifferent carbon atoms of the C₁-C₄ alkylene. In some embodiments, W is—CR^(W1)R^(W2)—. In some embodiments, W is —CH₂—CR^(W1)R^(W2)—. In someembodiments, W is —CH₂CH₂—CR^(W1)R^(W2)—. In some of these embodiments,each R^(W1) and R^(W2) is independently C₁-C₆ alkyl optionallysubstituted by R^(10A). In some of these embodiments, each R^(W1) andR^(W2) is independently C₁-C₆ alkyl (e.g., methyl).

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a) or any variation thereof, or asalt or solvate thereof, X is —CR^(X1)R^(X2)—. R^(X1) is hydrogen, C₁-C₆alkyl optionally substituted by R^(10A), or taken together with R⁷, R⁸,R^(Y1) or R^(W1), where present, to form a C₁-C₆ alkylene optionallysubstituted by R¹⁰, or taken together with R^(X2), R^(Y1), R^(Y2), R⁸,R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, or taken together with R^(W1),R^(W2), where present, R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms towhich they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰. R^(X2) is hydrogen or C₁-C₆ alkyl optionallysubstituted by R^(10A), or taken together with R^(X1), R^(Y1), R^(Y2),R⁸, R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, or taken together with R^(W1),R^(W2), where present, R^(X1), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms towhich they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰, or taken together with R⁸ to form a C₁-C₆ alkyleneoptionally substituted by R¹⁰.

In some embodiments, each R^(X1) and R^(X2) is independently hydrogen orC₁-C₆ alkyl optionally substituted by R^(10A). In some embodiments, eachR^(X1) and R^(X2) is independently hydrogen or C₁-C₆ alkyl (e.g.,methyl). In some embodiments, each R^(X1) and R^(X2) is hydrogen. Insome embodiments, each R^(X1) and R^(X2) is methyl. In some embodiments,R^(X1) is taken together with R⁷, R⁸, R^(Y1) or R^(W1), where present,to form a C₁-C₆ alkylene optionally substituted by R¹⁰.

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a) or any variation thereof, or asalt or solvate thereof, Y is —CR^(Y1)R^(Y2)—. R^(Y1) is hydrogen, C₁-C₆alkyl optionally substituted by R^(10A), or taken together with R⁷, R⁸,R^(X1) or R^(W1), where present, to form a C₁-C₆ alkylene optionallysubstituted by R¹⁰, or taken together with R^(Y2), R⁸, R⁹ and the atomsto which they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰, or taken together with R^(X1), R^(X2), R^(Y2), R⁸,R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, or taken together with R^(W1),R^(W2), where present, R^(X1), R^(X2), R^(Y2), R⁸, R⁹ and the atoms towhich they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰. R^(Y2) is hydrogen, C₁-C₆ alkyl optionallysubstituted by R^(10A), or taken together with R^(Y1), R⁸, R⁹ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(X1), R^(X2),R^(Y1), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(W1), R^(W2), where present, R^(X1), R^(X2), R^(Y1), R⁸,R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, or taken together with R⁸ toform a C₁-C₆ alkylene optionally substituted by R¹⁰.

In some embodiments, each R^(Y1) and R^(Y2) is independently hydrogen orC₁-C₆ alkyl optionally substituted by R¹⁰. In some embodiments, eachR^(Y1) and R^(Y2) is independently hydrogen or C₁-C₆ alkyl (e.g.,methyl). In some embodiments, each R^(Y1) and R^(Y2) is hydrogen. Insome embodiments, each R^(Y1) and R^(Y2) is methyl. In some embodiments,R^(Y1) is taken together with R⁷, R⁸, R^(X1) or R^(W1), where present,to form a C₁-C₆ alkylene optionally substituted by R¹⁰.

In some embodiments, R⁷ and R^(Y1) are taken together to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R⁷ andR^(Y1) are taken together to form a C₁-C₆ alkylene. In some embodiments,R⁷ and R^(Y1) are taken together to form a C₁-C₄ alkylene optionallysubstituted by R¹⁰. In some embodiments, R⁷ and R^(Y1) are takentogether to form a C₁-C₄ alkylene. In some embodiments, R⁷ and R^(Y1)are taken together to form a methylene (—CH₂—) or ethylene (—CH₂CH₂—).

In some embodiments, R⁷ and R^(X1) are taken together to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R⁷ andR^(X1) are taken together to form a C₁-C₆ alkylene. In some embodiments,R⁷ and R^(X1) are taken together to form a C₁-C₄ alkylene optionallysubstituted by R¹⁰. In some embodiments, R⁷ and R^(X1) are takentogether to form a C₁-C₄ alkylene. In some embodiments, R⁷ and R^(X1)are taken together to form a methylene (—CH₂—) or ethylene (—CH₂CH₂—).

In some embodiments, R⁸ and R^(X1) are taken together to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R⁸ andR^(X1) are taken together to form a C₁-C₆ alkylene. In some embodiments,R⁸ and R^(X1) are taken together to form a C₁-C₄ alkylene optionallysubstituted by R¹⁰. In some embodiments, R⁸ and R^(X1) are takentogether to form a C₁-C₄ alkylene. In some embodiments, R⁸ and R^(X1)are taken together to form a methylene (—CH₂—) or ethylene (—CH₂CH₂—).

In some embodiments, R⁸ and R^(Y1) are taken together to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R⁸ andR^(Y1) are taken together to form a C₁-C₆ alkylene. In some embodiments,R⁸ and R^(Y1) are taken together to form a C₁-C₄ alkylene optionallysubstituted by R¹⁰. In some embodiments, R⁸ and R^(Y1) are takentogether to form a C₁-C₄ alkylene. In some embodiments, R⁸ and R^(Y1)are taken together to form a propylene (—CH₂CH₂CH₂—) or ethylene(—CH₂CH₂—).

In some embodiments, R⁸ and R^(W1) are taken together to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R⁸ andR^(W1) are taken together to form a C₁-C₆ alkylene. In some embodiments,R⁸ and R^(W1) are taken together to form a C₁-C₄ alkylene optionallysubstituted by R¹⁰. In some embodiments, R⁸ and R^(W1) are takentogether to form a C₁-C₄ alkylene. In some embodiments, R⁸ and R^(W1)are taken together to form a methylene (—CH₂—) or ethylene (—CH₂CH₂—).

In some embodiments, R^(Y1) and R^(W1) are taken together to form aC₁-C₆ alkylene optionally substituted by R¹⁰. In some embodiments,R^(Y1) and R^(W1) are taken together to form a C₁-C₆ alkylene. In someembodiments, R^(Y1) and R^(W1) are taken together to form a C₁-C₄alkylene optionally substituted by R¹⁰. In some embodiments, R^(Y1) andR^(W1) are taken together to form a C₁-C₄ alkylene. In some embodiments,R^(Y1) and R^(W1) are taken together to form a methylene (—CH₂—) orethylene (—CH₂CH₂—).

In some embodiments, R^(Y1), R^(Y2), R⁸ and R⁹ are taken together withthe atoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰. In some embodiments, R^(Y), R^(Y2), R⁸and R⁹ are taken together with the atoms to which they are attached toform a 5- or 6-membered heteroaryl (e.g., 4-imidazolyl or 2-pyridyl)optionally substituted by R¹⁰. In some embodiments, R^(Y1), R^(Y2), R⁸and R⁹ are taken together with the atoms to which they are attached toform imidazol-4-yl.

In some embodiments, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ are takentogether with the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰. In someembodiments, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ are taken togetherwith the atoms to which they are attached to form a 5- or 6-memberedheteroaryl (e.g., 2-pyridyl) optionally substituted by R¹⁰. In someembodiments, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ are taken togetherwith the atoms to which they are attached to form pyridin-3-yl.

In some embodiments, R^(X2) is taken together with R⁸ to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R^(X2) andR⁸ are taken together to form a C₁-C₄ alkylene optionally substituted byR¹⁰. In some embodiments, R^(X2) and R⁸ are taken together to form apropylene (—CH₂CH₂CH₂—), ethylene (—CH₂CH₂—), or methylene (—CH₂—).

In some embodiments, W is C₁-C₄ alkylene substituted by R^(W1) andR^(W2), and R^(W1), R^(W2), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ aretaken together with the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰. In someembodiments, R^(W1), R^(W2), R^(X1)R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ aretaken together with the atoms to which they are attached to form a 5- or6-membered heteroaryl (e.g., 4-pyridyl) optionally substituted by R¹⁰.In some embodiments, R^(W1), R^(W2), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸,R⁹ are taken together with the atoms to which they are attached to formpyridin-4-yl. In some embodiments, W is a bond (or absent).

In some embodiments, R^(W1) is taken together with R⁸ to form a C₁-C₆alkylene optionally substituted by R¹⁰. In some embodiments, R^(W1) andR⁸ are taken together to form a C₁-C₄ alkylene optionally substituted byR¹⁰. In some embodiments, R^(W1) and R⁸ are taken together to form apropylene (—CH₂CH₂CH₂—), ethylene (—CH₂CH₂—), or methylene (—CH₂—).

In some embodiments, R⁷ and R^(Y1), R^(X1) or R^(W1), where present, aretaken together to form a C₁-C₆ alkylene substituted by R¹⁰, and R⁸ istaken together with R¹⁰ to form a C₁-C₆ alkylene, to form a fusedbicyclic moiety. In some embodiments, R⁷ and R^(Y1), R^(X1) or R^(W1),where present, are taken together to form a C₁-C₄ alkylene substitutedby R¹⁰, and R⁸ is taken together with R¹⁰ to form a C₁-C₄ alkylene. Insome embodiments, R⁷ and R^(Y1), R^(X1) or R^(W1), where present, aretaken together to form a methylene or ethylene substituted by R¹⁰, andR⁸ is taken together with R¹⁰ to form a methylene or ethylene. In oneembodiment, R⁷ and R^(X1) are taken together to form an ethylenesubstituted by R¹⁰, and R⁸ is taken together with R¹⁰ to form amethylene.

In some embodiments, R⁷ and R^(X1) are taken together to form a C₁-C₆alkylene optionally substituted by R¹⁰, and R⁸ is taken together withR^(X2) to form a C₁-C₆ alkylene, to form a spiro bicyclic moiety. Insome embodiments, R⁷ and R^(X1) are taken together to form a C₁-C₄alkylene optionally substituted by R¹⁰, and R⁸ is taken together withR^(X2) to form a C₁-C₄ alkylene. In some embodiments, R⁷ and R^(X1) aretaken together to form a methylene or ethylene, and R⁸ is taken togetherwith R^(X2) to form a methylene or ethylene. In one embodiment, R⁷ andR^(X1) are taken together to form an ethylene, and R⁸ and R^(X2) aretaken together to form a methylene.

In some embodiments of the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or asalt or solvate thereof, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety or the—[N(R⁷)—W—X—Y]_(m)—N(R⁸)R⁹ moiety, where applicable, is selected fromthe group consisting of:

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is selected fromthe group consisting

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is selected fromthe group consisting of:

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is selected fromthe group consisting of:

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety selected from thegroup consisting of:

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁷)R⁹ moiety is selected fromthe group consisting of:

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is selected fromthe group consisting of:

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is selected fromthe group consisting of:

In some embodiments, the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is selected fromthe group consisting of:

In some embodiments, the —[N(R⁷)—W—X—Y]_(m)—N(R⁷)R⁹ moiety, where k is0, is

It is intended and understood that each and every variation of ring A¹,A², A³, A⁴, A⁵; i, j, U and V described herein, may be combined witheach and every variation of R¹, R³, R⁶, R⁷, R⁸, R⁹, W, X, Y, Z, m and ndescribed herein, the same as if each and every combination isindividually and specifically described. For example, in someembodiments, A¹ is N, A² is CR², A³ is N, A⁴ is N, A⁵ is N; i is 2, is1; U is a bond; V is a bond or ethylene (—CH₂CH₂—); R¹ is phenyloptionally substituted by R^(10A) (e.g., 4-methylphenyl or4-chlorophenyl); R² is hydrogen or C₁-C₆ alkyl (e.g., methyl); R³ ishydrogen or C₁-C₆ alkyl (e.g., methyl), n is 0, 1 or 2; each R⁶ isindependently C₁-C₆ alkyl, Z is C, m is 1, and the —N(R⁷)—W—X—Y—N(R⁸)R⁹moiety is selected from the group consisting of:

In some of these embodiments, R¹ is phenyl optionally substituted byC₁-C₆ alkyl or halo. In some of these embodiments, R² is hydrogen ormethyl. In some of these embodiments, R² is trifluoromethyl. In some ofthese embodiments, R² is phenyl. In some of these embodiments, R³ ishydrogen or methyl. In some of these embodiments, R³ is CF₃. In some ofthese embodiments, R³ is halo (e.g., chloro or iodo). In some of theseembodiments, R³ is phenyl. In some of these embodiments, V is a bond. Insome of these embodiments, V is a bond. In some of these embodiments, nis 0.

When a group or moiety is optionally substituted by R¹⁰ or R^(10A),unless otherwise specified, the group or moiety may be unsubstituted orsubstituted by one or more (e.g., 1, 2, 3, 4 or 5) applicablesubstituents independently selected from the groups listed for R¹⁰ orR^(10A). In one embodiment, a group or moiety optionally substituted byR¹⁰ or R^(10A) has one substituent selected from the groups listed forR¹⁰ or R^(10A). In another embodiment, a group or moiety optionallysubstituted by R¹⁰ or R^(10A) has two substituents independentlyselected from the groups listed for R¹⁰ or R^(10A). In anotherembodiment, a group or moiety optionally substituted by R¹⁰ or R^(10A)has three substituents independently selected from the groups listed forR¹⁰ or R^(10A). In another embodiment, a group or moiety optionallysubstituted by R¹⁰ or R^(10A) has four substituents independentlyselected from the groups listed for R¹⁰ or R^(10A). In some embodiments,a group or moiety optionally substituted by R¹⁰ or R^(10A) has 1 to 2, 1to 3, 1 to 4 or 1 to 5 substituents independently selected from thegroups listed for R¹⁰ or R^(10A).

In some embodiments, each optional substituent R¹⁰ is independentlyC₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl,3-12-membered heterocyclyl, 5-10-membered heteroaryl, C₆-C₁₄ aryl,halogen, —CN, —OR¹¹, —SR¹¹, —NR¹²R¹³, —NO₂, —C═NH(OR¹¹), —C(O)R¹¹,—OC(O)R¹¹, —C(O)OR¹¹, —C(O)NR¹²R¹³, —NR¹¹C(O)R¹², —NR¹¹C(O)OR¹²,—NR¹¹C(O)NR¹²R¹³, —S(O)R¹¹, —S(O)₂R¹¹, —NR¹¹S(O)R¹², —NR¹¹S(O)₂R¹²,—S(O)NR¹²R¹³, —S(O)₂NR¹²R¹³, or —P(O)(OR¹²⁾ (OR¹³); wherein the C₁-C₆alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl, 3-12-memberedheterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl of R¹⁰ areindependently optionally substituted by halogen, —CN, oxo, —OR¹⁴, —SR¹⁴,—NR¹⁴R¹⁵, —C(O)R¹⁴, —C(O)OR¹⁴, —S(O)R¹⁴, —S(O)₂R¹⁴, —P(O)(OR¹⁴)(OR¹⁵),3-12-membered heterocyclyl, 5-10-membered heteroaryl, C₆-C₁₄ aryl, C₃-C₈cycloalkyl, or C₁-C₆ alkyl optionally substituted by oxo, —OH orhalogen.

In some embodiments, each optional substituent R¹⁰ is independentlyC₁-C₆ alkyl, C₃-C₈ cycloalkyl, 3-12-membered heterocyclyl, 5-10-memberedheteroaryl, C₆-C₁₄ aryl, halogen, —CN, —OR¹¹, —NR¹²R¹³, —NO₂, or—C(O)R¹¹, wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, 3-12-memberedheterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl of R¹⁰ areindependently optionally substituted by halogen, —CN, oxo, or —OR¹⁴. Insome embodiments, each optional substituent R¹⁰ is independently halogen(e.g., F or Cl); —OR¹¹ (e.g., OCH₃); or C₁-C₆ alkyl (e.g., methyl)optionally substituted by halogen, —CN, oxo, —OR¹⁴.

In some embodiments, R¹⁰ is taken together with R⁸ to form a C₁-C₆alkylene. In some embodiments, R¹⁰ is taken together with R⁸ to form aC₁-C₄ alkylene. In some embodiments, R¹⁰ is taken together with R⁸ toform a propylene (—CH₂CH₂CH₂—), ethylene (—CH₂CH₂—), or methylene(—CH₂—).

In some embodiments, each R^(10A) is independently oxo or any variationdetailed herein for R¹⁰. In some embodiments, each R^(10A) isindependently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈cycloalkyl, 3-12-membered heterocyclyl, 5-10-membered heteroaryl, C₆-C₁₄aryl, halogen, —CN, —OR¹¹, —SR¹¹, —NR¹²R¹³, —NO₂, —C═NH(OR¹¹), —C(O)R¹¹,—OC(O)R¹¹, —C(O)OR¹¹, —C(O)NR¹²R¹³, —NR¹¹C(O)R¹², —NR¹¹C(O)OR¹²,—NR¹¹C(O)NR¹²R¹³, —S(O)R, —S(O)₂R, —NR¹¹S(O)R¹², —NR¹¹S(O)₂R¹²,—S(O)NR¹²R¹³, —S(O)₂NR¹²R¹³, or —P(O)(OR¹²) (OR¹³); wherein the C₁-C₆alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl, 3-12-memberedheterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl of R^(10A) areindependently optionally substituted by halogen, —CN, oxo, —OR¹⁴, —SR¹⁴,—NR¹⁴R¹⁵, —C(O)R¹⁴, —C(O)OR¹⁴, —S(O)R¹⁴, —S(O)₂R¹⁴, —P(O)(OR¹⁴)(OR¹⁵),3-12-membered heterocyclyl, 5-10-membered heteroaryl, C₆-C₁₄ aryl, C₃-C₈cycloalkyl, or C₁-C₆ alkyl optionally substituted by oxo, —OH orhalogen.

In some embodiments, each optional substituent R^(10A) is independentlyoxo, C₁-C₆ alkyl, C₃-C₈ cycloalkyl, 3-12-membered heterocyclyl,5-10-membered heteroaryl, C₆-C₁₄ aryl, halogen, —CN, —OR¹¹, —NR¹²R¹³,—NO₂, or —C(O)R¹¹, wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl,3-12-membered heterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl ofR^(10A) are independently optionally substituted by halogen, —CN, oxo,or —OR¹⁴. In some embodiments, each optional substituent R^(10A) isindependently oxo, halogen (e.g., F or Cl); —OR¹¹ (e.g., OCH₃); or C₁-C₆alkyl (e.g., methyl) optionally substituted by halogen, —CN, oxo, —OR¹⁴.

In some embodiments, R¹¹, R¹² and R¹³ are each independently hydrogen orC₁-C₆ alkyl. In some embodiments, R¹ is hydrogen. In some embodiments,R¹² and R¹³ are each hydrogen.

In some embodiments, R¹⁴ and R¹⁵ are each independently hydrogen orC₁-C₆ alkyl.

All variations referring to formula (I), where applicable, may applyequally to any of formula (A-I), (Ia), (I⁰), (I⁰a), (I⁰a-1), (I⁰a-2),(II), (IIa), (IIa-1), (IIa-1a), (IIa-1a-1), (IIa-1a-2), (IIa-1a-3),(IIa-1b), (IIa-1b-1), (IIa-1b-2), (IIa-1b-3), (IIa-1c), (IIa-1c-1),(IIa-1d), (IIa-1d-1), (IIa-1d-2), (IIa-1d-3), (IIa-1e), (IIa-1e-1),(IIa-1e-2), (IIa-1e-3), (IIa-1f), (IIa-1f-1), (IIa-1f-2), (IIa-1f-3),(III), (IIIa), (IV), (IV-a), (IV-a-1), (IV-a-2), (V), (V-a), (V-a-1),(V-a-2), (VI), (VI-a), (VI-a-1), (VI-a-2), (VII), (VII-a), (VII-a-1),(VII-a-2), (VIII), (VIII-a), (VIII-a-1), and (VIII-a-2) the same as ifeach and every variation were specifically and individually listed.Similarly, all variations referring to formula (I), where applicable,apply equally to all formulations and variations detailed herein, aswell as to all methods of use detailed herein.

Representative compounds are listed in Table 1.

TABLE 1 Compound No. Structure Chemical Name ¹  1

N-(3-(benzyl(methyl)amino)propyl)-1- (3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide  2

(4-benzylpiperazin-1-yl)(1-(3,4- dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4- yl)methanone  3

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(1-methylazetidin-3-yl)piperidine-4- carboxamide  4

N-(1-benzylazetidin-3-yl)-1-(3,4- dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4- carboxamide  5

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)piperidine-4- carboxamide  6

N-(3-(1H-imidazol-4-yl)propyl)-1- (3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide  7

N-(3-amino-2,2-dimethylpropyl)-1- (3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide  8

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(isopropylamino)ethyl)piperidine-4- carboxamide  9

3-(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)-N-(2- (dimethylamino)ethyl)propanamide 10

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-((1-methylazetidin-3- yl)methyl)piperidine-4-carboxamide 11

N-(3-(azetidin-1-yl)propyl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4- d]pyridazin-7-yl)piperidine-4-carboxamide 12

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)cyclobutyl)piperidine- 4-carboxamide 12a

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-((1r,3r)-3- (dimethylamino)cyclobutyl)piperidine- 4-carboxamide 12b

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-((1s,3s)-3- (dimethylamino)cyclobutyl)piperidine- 4-carboxamide 13

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)pyrrolidine-3- carboxamide 13a

(S)-1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)pyrrolidine-3- carboxamide 13b

(R)-1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)pyrrolidine-3- carboxamide 15

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)azetidine-3- carboxamide 16

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(isopropylamino)ethyl)piperidine-3- carboxamide 16a

(R)-1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(isopropylamino)ethyl)piperidine-3- carboxamide 16b

(S)-1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(isopropylamino)ethyl)piperidine-3- carboxamide 17

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(1-methylpyrrolidin-3-yl)piperidine-4- carboxamide 17a

(S)-1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(1-methylpyrrolidin-3-yl)piperidine-4- carboxamide 17b

(R)-1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(1-methylpyrrolidin-3-yl)piperidine-4- carboxamide 18

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(1-methylpiperidin-4-yl)piperidine-4- carboxamide 19

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)-2- methylpiperidine-4-carboxamide 19a

(2S,4S)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N- (3-(dimethylamino)propyl)-2-methylpiperidine-4-carboxamide 19b

(2R,4R)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N- (3-(dimethylamino)propyl)-2-methylpiperidine-4-carboxamide 19c

(2R,4S)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N- (3-(dimethylamino)propyl)-2-methylpiperidine-4-carboxamide 19d

(2S,4R)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N- (3-(dimethylamino)propyl)-2-methylpiperidine-4-carboxamide 20

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)-4- methylpiperidine-4-carboxamide 21

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)-3- methylpiperidine-4-carboxamide 21a

(3S,4S)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N- (3-(dimethylamino)propyl)-3-methylpiperidine-4-carboxamide 21b

(3R,4R)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N- (3-(dimethylamino)propyl)-3-methylpiperidine-4-carboxamide 21c

(3R,4S)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N- (3-(dimethylamino)propyl)-3-methylpiperidine-4-carboxamide 21d

(3S,4R)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N- (3-(dimethylamino)propyl)-3-methylpiperidine-4-carboxamide 22

2-(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)-N-(3- (dimethylamino)propyl)acetamide 23

1-(3,4-dimethyl-2-(pyridin-3-yl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3- (dimethylamino)propyl)piperidine-4-carboxamide 24

1-(3,4-dimethyl-2-(thiophen-3-yl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3- (dimethylamino)propyl)piperidine-4-carboxamide 25

1-(3,4-dimethyl-2-(tetrahydro-2H- pyran-4-yl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3- (dimethylamino)propyl)piperidine-4- carboxamide26

1-((3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)methyl)-N-(3- (dimethylamino)propyl)piperidine-4- carboxamide 27

N-(3-(dimethylamino)propyl)-1-(2- isopropyl-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 28

1-(3,4-dimethyl-2-(oxazol-4-yl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)piperidine-4- carboxamide 29

N-(3-(dimethylamino)propyl)-1-(2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 31

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(4-(dimethylamino)butyl)piperidine-4- carboxamide 32

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(5-(dimethylamino)pentyl)piperidine-4- carboxamide 34

N-(3-(dimethylamino)propyl)-1-(4- methyl-3-phenyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 35

N-(3-(dimethylamino)propyl)-1-(3- methyl-4-phenyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 36

1-(4-chloro-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3- (dimethylamino)propyl)piperidine-4-carboxamide 37

N-(3-(dimethylamino)propyl)-1-(3-methyl-2-(p-tolyl)-4-(trifluoromethyl)- 2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide 38

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(6-(dimethylamino)hexyl)piperidine-4- carboxamide 40

(4-ethylpiperazin-1-yl)(1-(2-(p-tolyl)- 2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)methanone 41

N-(3-(dimethylamino)propyl)-1-(4- iodo-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 42

N-(3-(dimethylamino)propyl)-1-(3- methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4- carboxamide 43

(4-(diethylamino)piperidin-1-yl)(1- (3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidin-4-yl)methanone 44

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(3- (dimethylamino)pyrrolidin-1- yl)methanone 44a

(S)-(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(3- (dimethylamino)pyrrolidin-1- yl)methanone 44b

(R)-(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(3- (dimethylamino)pyrrolidin-1- yl)methanone 45

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(3- ((dimethylamino)methyl)pyrrolidin-1- yl)methanone45a

(R)-(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(3- ((dimethylamino)methyl)pyrrolidin-1- yl)methanone45b

(S)-(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(3- ((dimethylamino)methyl)pyrrolidin-1- yl)methanone46

N-(2-(dimethylamino)ethyl)-1-(2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 47

N-(2-(dimethylamino)ethyl)-1-(2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide 47a

(S)-N-(2-(dimethylamino)ethyl)-1-(2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin- 7-yl)piperidine-3-carboxamide 47b

(R)-N-(2-(dimethylamino)ethyl)-1-(2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin- 7-yl)piperidine-3-carboxamide 48

1-(7-chloro-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-4-yl)-N-(3- (dimethylamino)propyl)piperidine-4-carboxamide 49

N-(3-(dimethylamino)propyl)-1-(4- methyl-2-(p-tolyl)-2H-indazol-7-yl)piperidine-4-carboxamide 50

N-(2-(dimethylamino)ethyl)-3-(1-(4- methyl-2-(p-tolyl)-2H-indazol-7-yl)piperidin-4-yl)propanamide 51

N-(3-(dimethylamino)propyl)-1-(4- methyl-2-(p-tolyl)-1H-pyrrolo[2,3-d]pyridazin-7-yl)piperidine-4- carboxamide 52

N-(2-(dimethylamino)ethyl)-3-(1-(4- methyl-2-(p-tolyl)-1H-pyrrolo[2,3-d]pyridazin-7-yl)piperidin-4- yl)propanamide 53

N-(3-(dimethylamino)propyl)-1-(1- methyl-2-(p-tolyl)-1H-benzo[d]imidazol-4-yl)piperidine-4- carboxamide 54

N-(2-(dimethylamino)ethyl)-3-(1-(1- methyl-2-(p-tolyl)-1H-benzo[d]imidazol-4-yl)piperidin-4- y)propanamide 55

N-(3-(dimethylamino)propyl)-1-(2-(p- tolyl)-2H-pyrazolo[4,3-c]pyridin-7-yl)piperidine-4-carboxamide 56

N-(2-(dimethylamino)ethyl)-3-(1-(2-(p-tolyl)-2H-pyrazolo[4,3-c]pyridin-7- yl)piperidin-4-yl)propanamide ¹Chemical names are generated using the ChemBioDraw ® Ultra version14.0.0.117 software.

Additional representative compounds are listed in Table 1-A.

TABLE 1-A Compound No. Structure Chemical Name ¹ 57

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-methylpyrrolidine-3-carboxamide 58

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(phenylamino)ethyl)piperidine-3- carboxamide 59

(4-(diethylamino)piperidin-1-yl)(1- (2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4- yl)methanone 60

(3-((dimethylamino)methyl)pyrrolidin- 1-yl)(1-(2-(p-tolyl)-2H-pyrazol[3,4-d]pyridazin-7- yl)piperidin-4-yl)methanone 61

N-(2-(dimethylamino)ethyl)-3-(1-(2- (p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4- yl)propanamide 62

N-(1-methylazetidin-3-yl)-1-(2-(p- tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide 63

N-(2-(dimethylamino)ethyl)-1-(4- methyl-2-(p-tolyl)-3-(trifluoromethyl)-2H-pyrazolo[3,4- d]pyridazin-7-yl)piperidine-4-carboxamide 64

N-(2-morpholinoethyl)-1-(2-(p- tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide 65

(4-(azetidin-1-yl)piperidin-1-yl)(1- (3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidin-4-yl)methanone 66

3-(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)-N-(1- methylazetidin-3-yl)propanamide 67

(4-(benzyl(methyl)amino)piperidin- 1-yl)(1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidin-4-yl)methanone 68

(3-((benzyl(methyl)amino)methyl) pyrrolidin-1-yl)(1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin- 7-yl)piperidin-4-yl)methanone 69

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4- morpholinopiperidin-1- yl)methanone 70

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(3- (morpholinomethyl)pyrrolidin-1 yl)methanone 71

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl) (hexahydropyrrolo[3,4-c]pyrrol- 2(1H)-yl)methanone 72

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(5- methylhexahydropyrrolo[3,4-c]pyrrol-2(1H)-yl)methano 73

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(2,7- diazaspiro[3.5]nonan-7- yl)methanone 74

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(2,6- diazaspiro[3.4]octan-6- yl)methanone 75

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(2-methyl-2,6- diazaspiro[3.4]octan-6- yl)methanone 76

4-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)piperazine- 1-carboxamide ¹ Chemical names aregenerated using the ChemBioDraw ® Ultra version 16.0.0.82 (68) software.

Additional compounds of the present disclosure are listed in Table 2.

TABLE 2 Compound No. Structure 2-1 

2-2 

2-3 

2-4 

2-5 

2-6 

2-7 

2-8 

2-9 

2-10

2-11

2-12

Certain compounds of Table 1X are listed in Table 3, with their chemicalstructure drawings and chemical names.

TABLE 3 Compound No. Structure Chemical Name ¹ 7x 

N-(3-(diethylamino)propyl)-1-(3,4- dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4- carboxamide 9x 

N-(3-(diethylamino)propyl)-1-(2-(4- methoxyphenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 17x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-morpholinoethyl)piperidine-4- carboxamide 19x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-morpholinopropyl)piperidine-4- carboxamide 20x

N-(2-(diethylamino)ethyl)-1-(3,4- dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 21x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(dimethylamino)ethyl)piperidine-4- carboxamide 24x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(2-methylpiperidin-1- yl)ethyl)piperidine-4-carboxamide 25x

N-(2-(butyl(ethyl)amino)ethyl)-1- (3,4-dimethyl-2-phenyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-4-carboxamide 31x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(4-methylpiperazin-1- yl)propyl)piperidine-4-carboxamide 32x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-morpholinoethyl)piperidine-4- carboxamide 33x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-((1-ethylpyrrolidin-2- yl)methyl)piperidine-4-carboxamide 45x

1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(dimethylamino)ethyl)piperidine-3- carboxamide 49x

1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-morpholinopropyl)piperidine-3- carboxamide 51x

(1-(3,4-dimethyl-2-(p-tolyl)-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4-ethylpiperazin-1- yl)methanone 54x

N-(2-(dimethylamino)ethyl)-1-(2-(4- methoxyphenyl)-3,4-dimethyl-2H-pyrazolo[3,4-d]pyridazin-7- yl)piperidine-3-carboxamide 59x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4-methylpiperazin- 1-yl)methanone 63x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-3-yl)(4-propylpiperazin- 1-yl)methanone 64x

(1-(3,4-dimethyl-2-phenyl-2H- pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)(4-propylpiperazin- 1-yl)methanone ¹ Chemical namesare generated using the ChemBioDraw ® Ultra version 14.0.0.117 or16.0.0.82 (68) software.

In some embodiments, provided is a compound selected from Compound Nos.1-56 in Table 1 or Compound Nos. 57-76 in Table 1-A, or a salt thereof.In some embodiments, the compound is selected from the group consistingof one or more of Compound Nos. 1-56 in Table 1, or a salt thereof. Insome embodiments, the compound is selected from the group consisting ofone or more of Compound Nos. 1-47 in Table 1, or a salt thereof. In someembodiments, provided is a compound selected from Compound Nos. 1, 2, 3,4, 5, 6, 7, 8, 9, 10, 11, 12, 12a, 12b, 13, 13a, 13b, 15, 16, 16a, 16b,17, 17a, 17b, 18, 19, 19a, 19b, 19c, 19d, 20, 21, 21a, 21b, 21c, 21d,22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 34, 35, 36, 37, 38, 40, 41, 42,43, 44, 44a, 44b, 45, 45a, 45b, 46, 47, 47a, 47b, 48, 49, 50, 51, 52,53, 54, 55 and 56 in Table 1, or a salt thereof. In some embodiments,the compound is selected from the group consisting of Compound Nos. 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12a, 12b, 13, 13a, 13b, 15, 16, 16a,16b, 17, 17a, 17b, 18, 19, 19a, 19b, 19c, 19d, 20, 21, 21a, 21b, 21c,21d, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 34, 35, 36, 37, 38, 40, 41,42, 43, 44, 44a, 44b, 45, 45a, 45b, 46, 47, 47a and 47b in Table 1, or asalt thereof. In some embodiments, the compound is selected from thegroup consisting of one or more of Compound Nos. 57-76 in Table 1-A, ora salt thereof. In some embodiments, provided is a compound selectedfrom the group consisting of Compound Nos. 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, and 76 in Table 1-A, ora salt thereof.

The invention also includes all salts of compounds referred to herein,such as pharmaceutically acceptable salts. The invention also includesany or all of the stereochemical forms, including any enantiomeric ordiastereomeric forms, and any tautomers or other forms of the compoundsdescribed. Unless stereochemistry is explicitly indicated in a chemicalstructure or name, the structure or name is intended to embrace allpossible stereoisomers of a compound depicted. In addition, where aspecific stereochemical form is depicted, it is understood that otherstereochemical forms are also embraced by the invention. All forms ofthe compounds are also embraced by the invention, such as crystalline ornon-crystalline forms of the compounds. It is also understood thatprodrugs, solvates and metabolites of the compounds are embraced by thisdisclosure. Compositions comprising a compound of the invention are alsointended, such as a composition of substantially pure compound,including a specific stereochemical form thereof. Compositionscomprising a mixture of compounds of the invention in any ratio are alsoembraced by the invention, including mixtures of two or morestereochemical forms of a compound of the invention in any ratio, suchthat racemic, non-racemic, enantioenriched and scalemic mixtures of acompound are embraced.

General Synthetic Methods

The compounds of the invention may be prepared by a number of processesas generally described below and more specifically in the Exampleshereinafter. In the following process descriptions, the symbols whenused in the formulae depicted are to be understood to represent thosegroups described above in relation to the formulae herein.

Where it is desired to obtain a particular enantiomer of a compound,this may be accomplished from a corresponding mixture of enantiomersusing any suitable conventional procedure for separating or resolvingenantiomers. Thus, for example, diastereomeric derivatives may beproduced by reaction of a mixture of enantiomers, e.g., a racemate, andan appropriate chiral compound. The diastereomers may then be separatedby any convenient means, for example by crystallization, and the desiredenantiomer recovered. In another resolution process, a racemate may beseparated using chiral High Performance Liquid Chromatography.Alternatively, if desired a particular enantiomer may be obtained byusing an appropriate chiral intermediate in one of the processesdescribed.

Chromatography, recrystallization and other conventional separationprocedures may also be used with intermediates or final products whereit is desired to obtain a particular isomer of a compound or tootherwise purify a product of a reaction.

Solvates and/or polymorphs of a compound provided herein or apharmaceutically acceptable salt thereof are also contemplated. Solvatescontain either stoichiometric or non-stoichiometric amounts of asolvent, and are often formed during the process of crystallization.Hydrates are formed when the solvent is water, or alcoholates are formedwhen the solvent is alcohol. Polymorphs include the different crystalpacking arrangements of the same elemental composition of a compound.Polymorphs usually have different X-ray diffraction patterns, infraredspectra, melting points, density, hardness, crystal shape, optical andelectrical properties, stability, and/or solubility. Various factorssuch as the recrystallization solvent, rate of crystallization, andstorage temperature may cause a single crystal form to dominate.

Compounds of the formula (I⁰a) can be prepared according to Scheme 1,wherein R⁶, i, j, n and V are as detailed herein for formula (I⁰a);R^(D) is R¹ as detailed herein for formula (I⁰a) or a protected formthereof; R^(C) is R² as detailed herein for formula (I⁰a) or a protectedform thereof; R^(B) is R³ as detailed herein for formula (I⁰a) or aprotected form thereof; and R^(A) is the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety asdetailed herein for formula (I⁰a) or a protected form thereof. In someembodiments, R^(D) is R¹ as detailed herein for formula (I⁰a). In onevariation, R^(D) is phenyl or p-tolyl. In some embodiments, R^(C) is R²as detailed herein for formula (I⁰a). In some embodiments, R^(B) is R³as detailed herein for formula (I⁰a). In some embodiments, R^(A) is the—N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety as detailed herein for formula (I⁰a).

Chlorination of a compound of Formula I-1 using a chlorinating agent(e.g., POCl₃) gives rise to a compound of Formula I-2. Displacement ofthe 7-chloro group in the compound of Formula I-2 with an azacyclicester of Formula I-5 yields a compound of Formula I-3, which can beconverted to a compound of Formula I-4 by hydrolysis using a base (e.g.,lithium hydroxide) in an aqueous solution. Amide coupling of a compoundof Formula I-4 and amine RAH using a peptide coupling agent (e.g., EDCIor HATU) provides a compounds of Formula (I⁰a).

Compounds of the formula (Ia) where U is methylene can be preparedaccording to Scheme 2, wherein R⁶, i, j, n and V are as detailed hereinfor formula (Ia); R^(D) is R¹ as detailed herein for formula (Ia) or aprotected form thereof; R^(C) is R² as detailed herein for formula (Ia)or a protected form thereof; R^(B) is R³ as detailed herein for formula(Ia) or a protected form thereof; and R^(A) is the —N(R⁷)—W—X—Y—N(R⁸)R⁹moiety as detailed herein for formula (Ia) or a protected form thereof.In some embodiments, R^(D) is R¹ as detailed herein for formula (Ia). Inone variation, R^(D) is phenyl or p-tolyl. In some embodiments, R^(C) isR² as detailed herein for formula (Ia). In some embodiments, R^(B) is R³as detailed herein for formula (Ia). In some embodiments, R^(A) is the—N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety as detailed herein for formula (Ia).

Chlorination of a compound of Formula Ia-1 using a chlorinating agent(e.g., POCl₃) gives rise to a compound of Formula Ia-2. Carboxylation atthe 7-position followed by reduction gives the 7-carboxyaldehyde ofFormula Ia-22. Coupling of the 7-carboxyaldehyde of Formula Ia-22 withan azacyclic ester of Formula I-5 (e.g., via reductive amination) yieldsa compound of Formula Ia-3 where U is methylene, which can be convertedto a compound of Formula Ia-4 by hydrolysis using a base (e.g., lithiumhydroxide) in an aqueous solution. Amide coupling of a compound ofFormula Ia-4 and amine R^(A)H using a peptide coupling agent (e.g., EDCIor HATU) provides a compound of Formula (Ia).

Compounds of formula (IV-a) can be prepared according to Scheme 3,wherein R⁶, i, j and n are as detailed herein for formula (IV-a); R^(D)is R¹ as detailed herein for formula (IV-a) or a protected form thereof;R^(B) is R³ as detailed herein for formula (IV-a) or a protected formthereof; R^(E) is R³⁰ as detailed herein for formula (IV-a) or aprotected form thereof; and R^(A) is the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety asdetailed herein for formula (IV-a) or a protected form thereof. In someembodiments, R^(D) is R¹ as detailed herein for formula (IV-a). In onevariation, R^(D) is phenyl or p-tolyl. In some embodiments, R^(B) is R³as detailed herein for formula (IV-a). In one variation, R^(B) is ahalogen (e.g., chloro). In some embodiments, R^(E) is R³⁰ as detailedherein for formula (IV-a). In one variation, R^(E) is methyl. In someembodiments, R^(A) is the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety as detailed hereinfor formula (IV-a).

Coupling of a compound of Formula IVa-1 with a compound of Formula IVa-2in the presence of a base (e.g. TEA) provides a compound of Formula(IV-a).

Compounds of formula (VII-a) can be prepared according to Scheme 4,wherein R⁶, i, j and n are as detailed herein for formula (VII-a); R^(D)is R¹ as detailed herein for formula (VII-a) or a protected formthereof; R^(C) is R^(2a) as detailed herein for formula (VII-a) or aprotected form thereof; R^(B) is R³ as detailed herein for formula(VII-a) or a protected form thereof; R^(F) is R⁴ as detailed herein forformula (VII-a) or a protected form thereof; R^(G) is R⁵ as detailedherein for formula (VII-a) or a protected form thereof; and R^(A) is the—N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety as detailed herein for formula (VII-a) or aprotected form thereof. In some embodiments, R^(D) is R¹ as detailedherein for formula (VII-a). In one variation, R^(D) is phenyl orp-tolyl. In some embodiments, R^(C) is R^(2a) as detailed herein forformula (VII-a). In one variation, R^(C) is a C₁-C₆ alkyl (e.g.,methyl). In some embodiments, R^(B) is R³ as detailed herein for formula(VII-a). In one variation, R^(B) is hydrogen. In some embodiments, R^(F)is R⁴ as detailed herein for formula (VII-a). In one variation, R^(F) ishydrogen. In some embodiments, R^(G) is R⁵ as detailed herein forformula (VII-a). In one variation, R^(G) is hydrogen. In someembodiments, R^(A) is the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety as detailed hereinfor formula (VII-a).

Coupling of a compound of Formula VIIa-1 with an azacyclic ester ofFormula VIIa-2 (e.g., in the presence of a palladium catalyst) yields acompound of Formula VIIa-3, which can be converted to a compound ofFormula VIIa-4 by hydrolysis using a base (e.g., lithium hydroxide).Amide coupling of a compound of Formula VIIa-4 and amine R^(A)H using apeptide coupling agent (e.g., EDCI) provides a compound of Formula(VII-a).

Compounds of formula (VIII-a) can be prepared according to Scheme 5,wherein R⁶, i, j and n are as detailed herein for formula (VIII-a);R^(D) is R¹ as detailed herein for formula (VIII-a) or a protected formthereof; R^(C) is R² as detailed herein for formula (VIII-a) or aprotected form thereof; R^(B) is R³ as detailed herein for formula(VIII-a) or a protected form thereof; R^(G) is R⁵ as detailed herein forformula (VIII-a) or a protected form thereof; and R^(A) is the—N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety as detailed herein for formula (VIII-a) or aprotected form thereof. In some embodiments, R^(D) is R¹ as detailedherein for formula (VIII-a). In one variation, R^(D) is phenyl orp-tolyl. In some embodiments, R^(C) is R² as detailed herein for formula(VIII-a). In one variation, R^(C) is hydrogen. In some embodiments,R^(B) is R³ as detailed herein for formula (VIII-a). In one variation,R^(B) is hydrogen. In some embodiments, R^(G) is R⁵ as detailed hereinfor formula (VIII-a). In one variation, R^(G) is hydrogen. In someembodiments, R^(A) is the —N(R⁷)—W—X—Y—N(R⁷)R⁹ moiety as detailed hereinfor formula (VIII-a).

Coupling of a compound of Formula VIIIa-1 with an azacyclic ester ofFormula VIIIa-2 (e.g., in the presence of a palladium catalyst) yields acompound of Formula VIIIa-3, which can be converted to a compound ofFormula VIIIa-4 by hydrolysis using a base (e.g., lithium hydroxide).Amide coupling of a compound of Formula VIIIa-4 and amine R^(A)H using apeptide coupling agent (e.g., HATU) provides a compound of Formula(VIII-a).

Pharmaceutical Compositions and Formulations

Pharmaceutical compositions of any of the compounds detailed herein areembraced by this invention, for example, a compound of formula (A-I)(I),(Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a),(VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereofdetailed herein, or a salt or solvate thereof. Thus, the inventionincludes pharmaceutical compositions comprising a compound of formula(A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a),(V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or anyvariation thereof detailed herein, or a pharmaceutically acceptable saltthereof and a pharmaceutically acceptable excipient. In someembodiments, the compound is selected from Compound Nos. 1-56 in Table1, or a salt (e.g., a pharmaceutically acceptable salt) or solvatethereof. In some embodiments, the compound is selected from CompoundNos. 57-76 in Table 1-A, or a salt (e.g., a pharmaceutically acceptablesalt) or solvate thereof. In some embodiments, the compound includes acompound listed in Table 1X, or a salt or solvate thereof. In someembodiments, the compound does not include a compound listed in Table1X, and salts and solvates thereof. In some embodiments, the compound isa compound listed in Table 3, or a salt (e.g., a pharmaceuticallyacceptable salt) or solvate thereof. In some embodiments, the compoundis selected from the group consisting of Compound Nos. 7x, 9x, 17x, 19x,20x, 21x, 24x, 25x, 31x, 32x, 33x, 45x, 49x, 51x, 54x, 59x, 63x, 64x,and salts and solvates thereof.

In one aspect, the pharmaceutically acceptable salt is an acid additionsalt, such as a salt formed with an inorganic or organic acid.

A compound as detailed herein may in one aspect be in a purified formand compositions comprising a compound in purified forms are detailedherein. Compositions comprising a compound as detailed herein or a saltthereof are provided, such as compositions of substantially purecompounds. In some embodiments, a composition containing a compound asdetailed herein or a salt thereof is in substantially pure form. In onevariation, “substantially pure” intends a composition that contains nomore than 35% impurity, wherein the impurity denotes a compound otherthan the compound comprising the majority of the composition or a saltthereof. For example, a composition of a substantially pure compoundselected from a compound of Table 1 intends a composition that containsno more than 35% impurity, wherein the impurity denotes a compound otherthan the compound or a salt thereof. In one variation, a composition ofsubstantially pure compound or a salt thereof is provided wherein thecomposition contains no more than 25% impurity. In another variation, acomposition of substantially pure compound or a salt thereof is providedwherein the composition contains or no more than 20% impurity. In stillanother variation, a composition of substantially pure compound or asalt thereof is provided wherein the composition contains or no morethan 10% impurity. In a further variation, a composition ofsubstantially pure compound or a salt thereof is provided wherein thecomposition contains or no more than 5% impurity. In another variation,a composition of substantially pure compound or a salt thereof isprovided wherein the composition contains or no more than 3% impurity.In still another variation, a composition of substantially pure compoundor a salt thereof is provided wherein the composition contains or nomore than 1% impurity. In a further variation, a composition ofsubstantially pure compound or a salt thereof is provided wherein thecomposition contains or no more than 0.5% impurity. In yet othervariations, a composition of substantially pure compound means that thecomposition contains no more than 15% or preferably no more than 10% ormore preferably no more than 5% or even more preferably no more than 3%and most preferably no more than 1% impurity, which impurity may be thecompound in a different stereochemical form. For instance, a compositionof substantially pure (S) compound means that the composition containsno more than 15% or no more than 10% or no more than 5% or no more than3% or no more than 1% of the (R) form of the compound.

In one variation, the compounds herein are synthetic compounds preparedfor administration to an individual such as a human. In anothervariation, compositions are provided containing a compound insubstantially pure form. In another variation, the invention embracespharmaceutical compositions comprising a compound detailed herein and apharmaceutically acceptable excipient. In another variation, methods ofadministering a compound are provided. The purified forms,pharmaceutical compositions and methods of administering the compoundsare suitable for any compound or form thereof detailed herein.

The compound may be formulated for any available delivery route,including an oral, mucosal (e.g., nasal, sublingual, vaginal, buccal orrectal), parenteral (e.g., intramuscular, subcutaneous or intravenous),topical or transdermal delivery form. A compound may be formulated withsuitable excipients to provide delivery forms that include, but are notlimited to, tablets, caplets, capsules (such as hard gelatin capsules orsoft elastic gelatin capsules), cachets, troches, lozenges, gums,dispersions, suppositories, ointments, cataplasms (poultices), pastes,powders, dressings, creams, solutions, patches, aerosols (e.g., nasalspray or inhalers), gels, suspensions (e.g., aqueous or non-aqueousliquid suspensions, oil-in-water emulsions or water-in-oil liquidemulsions), solutions and elixirs.

One or several compounds described herein can be used in the preparationof a formulation, such as a pharmaceutical formulation, by combining thecompound or compounds as an active ingredient with a pharmaceuticallyacceptable excipient, such as those mentioned above. Depending on thetherapeutic form of the system (e.g., transdermal patch vs. oraltablet), the excipient may be in various forms. In addition,pharmaceutical formulations may contain preservatives, solubilizers,stabilizers, re-wetting agents, emulgators, sweeteners, dyes, adjusters,and salts for the adjustment of osmotic pressure, buffers, coatingagents or antioxidants. Formulations comprising the compound may alsocontain other substances which have valuable therapeutic properties.Pharmaceutical formulations may be prepared by known pharmaceuticalmethods. Suitable formulations can be found, e.g., in Remington: TheScience and Practice of Pharmacy, Lippincott Williams & Wilkins, 21^(st)ed. (2005), which is incorporated herein by reference.

Compounds as described herein may be administered to individuals (e.g.,a human) in a form of generally accepted oral compositions, such astablets, coated tablets, and gel capsules in a hard or in soft shell,emulsions or suspensions. Examples of excipients, which may be used forthe preparation of such compositions, are lactose, corn starch or itsderivatives, talc, stearate or its salts, etc. Acceptable excipients forgel capsules with soft shell are, for instance, plant oils, wax, fats,semisolid and liquid poly-ols, and so on. In addition, pharmaceuticalformulations may contain preservatives, solubilizers, stabilizers,re-wetting agents, emulgators, sweeteners, dyes, adjusters, and saltsfor the adjustment of osmotic pressure, buffers, coating agents orantioxidants.

Any of the compounds described herein can be formulated in a tablet inany dosage form described, for example, a compound as described hereinor a pharmaceutically acceptable salt thereof can be formulated as a 1,5, 10, 20, 50, 100, 250 or 500 mg tablet.

Compositions comprising a compound provided herein are also described.In one variation, the composition comprises a compound and apharmaceutically acceptable excipient. In another variation, acomposition of substantially pure compound is provided.

Methods of Use

Compounds and compositions of the present disclosure, such as apharmaceutical composition comprising a compound of formula (A-I), (I),(Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a),(VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereofdetailed herein, or a pharmaceutically acceptable salt thereof and apharmaceutically acceptable excipient, are suitable for a plurality ofuses involving inhibiting one or both of a toll-like receptor 8(TLR8)-dependent response and a toll-like receptor 9 (TLR9)-dependentresponse in an individual in need thereof. The individual in need mayhave an immunological disorder such as an autoimmune disease or aninflammatory disease. In some instances, the individual in need may havea chronic or an acute pathogen infection. In other instance, theindividual may have cancer. In particular, the pharmaceuticalcompositions of the present disclosure comprising a compound of formula(A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a),(V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or anyvariation thereof detailed herein, or a pharmaceutically acceptable saltthereof, are suitable for inhibiting an immune response in an individualin need thereof. The individual of the present disclosure is a mammaliansubject. Mammalian subjects include but are not limited to humans,nonhuman primates, rodents, pets, and farm animals. The pharmaceuticalcomposition is administered to the individual in an amount effective toachieve a specific outcome.

A. Inhibition of an Immune Response and Treatment of Cancer

Provided herein are methods of inhibiting an immune response in anindividual comprising administering to the individual an amount of acompound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III),(IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof detailed herein, or apharmaceutically acceptable salt thereof, effective to inhibit theimmune response in the individual. In some embodiments, the compound ispresent in a pharmaceutical composition comprising a pharmaceuticallyacceptable excipient. The individual of the methods of the presentdisclosure is a mammal, which in some embodiments is a human while inother embodiments is a nonhuman primate or a rodent. “Inhibiting” animmune response refers to decreasing the immune response of mammalianleukocytes (e.g., peripheral blood mononuclear cells, monocytes, Bcells, plasmacytoid dendritic cells, etc.). In some embodiments, immuneresponses inhibited include inhibition of cytokine production,inhibition of cell maturation and/or inhibition of cell proliferation.In some embodiments, inhibiting an immune response comprises one or moreof the group consisting of: inhibiting tumor necrosis factor-alphaproduction; inhibiting interleukin-1beta production; inhibitinginterleukin-6 production; and inhibiting interferon-alpha production. Insome embodiments, the compound is selected from Compound Nos. 1-56 inTable 1, or a pharmaceutically acceptable salt thereof. In someembodiments, the compound is selected from Compound Nos. 1-47 in Table1, or a pharmaceutically acceptable salt thereof. In some embodiments,the compound is selected from Compound Nos. 57-76 in Table 1-A, or apharmaceutically acceptable salt thereof. In some embodiments, thecompound includes a compound listed in Table 1X, or a pharmaceuticallyacceptable salt thereof. In some embodiments, the compound does notinclude a compound listed in Table 1X, and pharmaceutically acceptablesalts thereof. In some embodiments, the compound includes a compoundlisted in Table 3, or a pharmaceutically acceptable salt thereof.

In some embodiments, the immune response comprises one or both of aTLR8-dependent immune response and a TLR9-dependent immune response, andthe pharmaceutical composition is administered in an amount effective toinhibit one or both of the TLR8-dependent immune response and theTLR9-dependent immune response in the individual. In some preferredembodiments, the immune response comprises a TLR8-dependent immuneresponse and the pharmaceutical composition is administered in an amounteffective to inhibit the TLR8-dependent immune response in theindividual. In some preferred embodiments, the immune response comprisesa TLR9-dependent immune response and the pharmaceutical composition isadministered in an amount effective to inhibit the TLR9-dependent immuneresponse in the individual. In some embodiments, the pharmaceuticalcomposition is administered in an amount effective to inhibit theTLR8-dependent immune response but not a TLR9-dependent immune responsein the individual. In other embodiments, the pharmaceutical compositionis administered in an amount effective to inhibit the TLR9-dependentimmune response but not a TLR8-dependent immune response in theindividual.

The present disclosure provides methods of inhibiting an immuneresponse, particularly those associated with an immunological disorder.The present disclosure also provides methods for ameliorating symptomsassociated with the immunological disorder. The methods of the presentdisclosure for inhibiting one or both of a TLR8-dependent and aTLR9-dependent immune response can be practiced in vitro, ex vivo or invivo. In some embodiments, a mammalian (e.g., human, nonhuman primate,rodent, etc.) cell is contacted with a compound of formula (I), or anyvariation thereof, e.g., a compound of formula (A-I), (Ia), (I⁰), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or a compound selected from CompoundNos. 1-56 in Table 1 or Compound Nos. 57-76 in Table 1-A, or apharmaceutically acceptable salt thereof, in an amount effective toinhibit a response by the cell that contributes to an immune response(e.g., secretion of a cytokine by the cell).

Inhibition of one or both of a TLR8-dependent and a TLR9-dependentresponse may be useful for treating and/or preventing a variety ofpathological conditions (e.g., immunological disorders) that areresponsive to cytokines. Pathological conditions for which a compound offormula (A-I) or (I), or any variation thereof, e.g., a compound offormula (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a),(V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or acompound selected from Compound Nos. 1-56 in Table 1 or Compound Nos.57-76 in Table 1-A, or a pharmaceutically acceptable salt thereof, maybe used as treatments include, but are not limited to autoimmunediseases, inflammatory diseases, chronic pathogen stimulation, acutepathogen stimulation, and cancer. Provided herein are methods oftreating or preventing an immunological disorder in an individualcomprising administering to the individual an effective amount of ancompound of formula (A-I) or (I), or any variation thereof, e.g., acompound of formula (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV),(IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or acompound selected from Compound Nos. 1-56 in Table 1 or Compound Nos.57-76 in Table 1-A, or a pharmaceutically acceptable salt thereof.Further, provided are methods for ameliorating symptoms associated withan immunological disorder comprising administering an effective amountof compound of formula (A-I) or (I), or any variation thereof, e.g., acompound of formula (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV),(IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or acompound selected from Compound Nos. 1-56 in Table 1 or Compound Nos.57-76 in Table 1-A, or a pharmaceutically acceptable salt thereof, to anindividual having the disorder. Methods are also provided for preventingor delaying development of an immunological disorder, comprisingadministering an effective amount of compound of formula (A-I) or (I),or any variation thereof, e.g., a compound of formula (Ia), (I⁰), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or a compound selected from CompoundNos. 1-56 in Table 1 or Compound Nos. 57-76 in Table 1-A, or apharmaceutically acceptable salt thereof, to an individual having thedisorder.

Provided herein are methods of inhibiting an immune response in anindividual, comprising administering to the individual a compound offormula (A-I) or (I), or any variation thereof, e.g., a compound offormula (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a),(V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or acompound selected from Compound Nos. 1-56 in Table 1 or Compound Nos.57-76 in Table 1-A, or a pharmaceutically acceptable salt thereof, in anamount effective to inhibit the immune response in the individual. Insome embodiments, the immune response is associated with an autoimmunedisease. In further embodiments, inhibiting the immune responseameliorates one or more symptoms of the autoimmune disease. In stillfurther embodiments, inhibiting the immune response treats theautoimmune disease. In yet further embodiments, inhibiting the immuneresponse prevents or delays development of the autoimmune disease. Insome embodiments, the autoimmune disease is selected from the groupconsisting of systemic lupus erythematosus, type I diabetes mellitus,multiple sclerosis, rheumatoid arthritis, inflammatory bowel disease,Sjogren's syndrome, scleroderma and dermatomyositis. In someembodiments, the inflammatory bowel disease is selected from the groupconsisting of Crohn's disease and ulcerative colitis.

The present disclosure provides methods of treating or preventing anautoimmune disease in an individual, comprising administering to theindividual an effective amount of a compound of formula (A-I) or (I), orany variation thereof, e.g., a compound of formula (Ia), (I⁰), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or a compound selected from CompoundNos. 1-56 in Table 1 or Compound Nos. 57-76 in Table 1-A, or apharmaceutically acceptable salt thereof. Autoimmune diseases arecharacterized by the production of antibodies that react with selfantigens of the individual and/or by the presence of immune effectorcells that react to cells of the individual displaying peptides derivedfrom the self antigens.

In some aspects, the autoimmune disease affects a major organ of theindividual, such as the heart, kidney or liver. Autoimmune diseases ofthe heart include for instance, autoimmune myocarditis, which is alsoreferred to as autoimmune cardiomyopathy and Coxsackie myocarditis.Autoimmune diseases of the kidney include but are not limited to lupusnephritis and anti-glomerular basement membrane nephritis, the latterwhich is also known as Goodpastures syndrome and glomerulonephritis typeI. Autoimmune diseases of the liver include for instance, autoimmunehepatitis and primary biliary cirrhosis.

In further aspects, the autoimmune disease affects the skin of theindividual. Autoimmune diseases of the skin include but are not limitedto alopecia areata, autoimmune urticaria, dematitis herpetiformis,pemphigus vulgaris, psoriasis, systemic scleroderma, the latter of whichis also known as systemic sclerosis and scleroderma.

In additional aspects, the autoimmune disease affects one or more glandsof the individual. Autoimmune diseases that affect endocrine glandsinclude for instance, Addison's disease, autoimmune polyendocrinesyndrome type 1 (Whitaker's syndrome), type 2 (Schmidt syndrome), andtype 3, autoimmune pancreatitis, diabetes mellitus type 1, autoimmunethyroiditis (Hashimoto's thyroiditis), and Graves' disease. Autoimmunediseases that affect exocrine glands include for example, Sjogren'ssyndrome.

In some aspects, the autoimmune disease affects the digestive system ofthe individual. Autoimmune diseases of the digestive system include butare not limited to celiac disease, Crohn' disease and ulcerativecolitis. Crohn' disease and ulcerative colitis are two types ofinflammatory bowel disease.

In further aspects, the autoimmune disease affects blood of theindividual. Autoimmune diseases of the blood include for instanceantiphospholipid syndrome (Hughes syndrome), autoimmune hemolyticanemia, autoimmune lymphoproliferative syndrome (Canale-Smith syndrome),idiopathic thrombocytopenic purpura, and pernicious anemia.

In additional aspects, the autoimmune disease affects connective tissueor is systemic or otherwise affects multiple tissues of the individual.Such autoimmune diseases include but are not limited to mixed connectivetissue disease, psoriatic arthritis, relapsing polychondritis,rheumatoid arthritis, systemic lupus erythematosus, and undifferentiatedconnective tissue disease.

In some aspects, the autoimmune disease affects muscle of theindividual. Autoimmune diseases of muscle include for instance,dermatomyositis, myasthenia gravis, and polymyositis.

In further aspects the autoimmune disease affects the nervous system ofthe individual. Autoimmune diseases of the nervous system include butare not limited to acute disseminated encephalomyelitis, Guillain Barresyndrome, Hashimoto's encephalopathy, and multiple sclerosis.

In additional aspects, the autoimmune disease affects the eyes or earsof the individual. Autoimmune uveitis is an exemplary autoimmune diseaseof the eye. Autoimmune inner ear disease is an exemplary autoimmunedisease of the ear.

In some aspects, the autoimmune disease affects the vascular system.Autoimmune diseases of the vascular system include for instance Behcet'sdisease, giant cell arteritis, and vasculitis.

Autoimmune diseases include, without limitation, rheumatoid arthritis,autoimmune pancreatitis, systemic lupus erythematosus (SLE), type Idiabetes mellitus, multiple sclerosis (MS), antiphospholipid syndrome(APS), sclerosing cholangitis, systemic onset arthritis, scleroderma,Sjogren's disease, vitiligo, polymyositis, pemphigus vulgaris, pemphigusfoliaceus, inflammatory bowel disease (IBD) including Crohn's diseaseand ulcerative colitis, autoimmune hepatitis, hypopituitarism,graft-versus-host disease, autoimmune skin diseases, uveitis, perniciousanemia, and hypoparathyroidism. Autoimmune diseases may also include,without limitation, polyangitis overlap syndrome, Kawasaki's disease,sarcoidosis, glomerulonephritis, and cryopathies. In some aspects, theautoimmune disease is selected from the group consisting of arthritis,pancreatitis, mixed connective tissue disease, lupus, antiphospholipidsyndrome, systemic onset arthritis, and irritable bowel syndrome. Inother aspects, the autoimmune disease is selected from the groupconsisting of systemic lupus erythematosus, rheumatoid arthritis,autoimmune skin disease, and multiple sclerosis. In other aspects, theautoimmune disease is selected from the group consisting ofpancreatitis, glomerulonephritis, pyelitis, sclerosing cholangitis, andtype I diabetes. In some aspects, the autoimmune disease is rheumatoidarthritis. In some aspects, the autoimmune disease is autoimmunepancreatitis. In some aspects, the autoimmune disease isglomerulonephritis. In some aspects, the autoimmune disease is pyelitis.In some aspects, the autoimmune disease is sclerosing cholangitis. Insome aspects the autoimmune disorder is psoriasis. In some aspects, theautoimmune disease is rheumatoid arthritis. In some aspects, theautoimmune disease is type I diabetes mellitus. In some aspects, theautoimmune disease is associated with RNA-containing immune complexes.In some aspects, the autoimmune disease is Sjogren's disease. In furtherembodiments, the autoimmune disease is selected from the groupconsisting of type I diabetes mellitus, multiple sclerosis, systemiclupus erythematosus, inflammatory bowel disease, rheumatoid arthritisand Sjogren's syndrome.

Provided herein are methods of inhibiting an immune response in anindividual, the method comprising administering to the individual acompound of formula (A-I) or (I), or any variation thereof, e.g., acompound of formula (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV),(IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or acompound selected from Compound Nos. 1-56 in Table 1 or Compound Nos.57-76 in Table 1-A, or a pharmaceutically acceptable salt thereof, in anamount effective to inhibit the immune response in the individual. Insome variations, the immune response is associated with an inflammatorydisease. The term “inflammatory disease” as used herein encompassesimmunological disorders lacking known autoimmune or infectiouscomponents. In further aspects, inhibiting the immune responseameliorates one or more symptoms of the inflammatory disease. In stillfurther aspects, inhibiting the immune response treats the inflammatorydisease. In yet further aspects, inhibiting the immune response preventsor delays development of the inflammatory disease. In some embodiments,the inflammatory disease is selected from the group consisting ofpancreatitis, kidney fibrosis, liver fibrosis, chronic kidney disease,alcohol-related fatty liver disease (such as alcohol-relatedsteatohepatitis, and non-alcoholic fatty liver disease (such asnonalcoholic steatohepatitis, also known as NASH). In other embodiments,the inflammatory disease is selected from the group consisting ofatherosclerosis, ischemia, ischemic-reperfusion injury, myocardialinjury and traumatic tissue injury.

In some aspects, the inflammatory disease is selected from the groupconsisting of non-rheumatoid arthritis, kidney fibrosis, and liverfibrosis. In some aspects, the inflammatory disease is an interfacedermatitis. In some further aspects, the interface dermatitis isselected from the group consisting of lichen planus, lichenoid eruption,lichen planus-like keratosis, lichen striatus, keratosis lichenoideschronica, erythema multiforme, fixed drug eruption, pityriasislichenoides, phototoxic dermatitis, radiation dermatitis, viralexanthems, dermatomyositis, secondary syphilis, lichen sclerosus etatrophicus, mycosis fungoides, bullous pemphigoid, lichen aureus,porokeratosis, acrodermatitis chronicus atrophicans, and regressingmelanoma. In some aspects, the inflammatory disease is a skin disordersuch as atopic dermatitis (eczema). In some aspects, the inflammatorydisease is a condition such as drug-induced liver and/or pancreasinflammation. In some further aspects, the inflammatory disease is aninflammatory liver disorder. In some other further aspects, theinflammatory disease is an inflammatory pancreatic disorder.

Also provided are methods of inhibiting an immune response associatedwith chromic or acute pathogen stimulation in an individual, comprisingadministering to the individual a compound of formula (A-I) or (I), orany variation thereof, e.g., a compound of formula (Ia), (I⁰), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or a compound selected from CompoundNos. 1-56 in Table 1 or Compound Nos. 57-76 in Table 1-A, or apharmaceutically acceptable salt thereof, in an amount effective toinhibit the immune response in the individual. In some embodiments, thechronic pathogen stimulation is due to parasitic infection. In someembodiments, the acute pathogen stimulation is due to a bacterialinfection. In some embodiments, the acute pathogen stimulation is due tosepsis.

Furthermore, methods of treating cancer in an individual with cancer areprovided, comprising administering to the individual a compound offormula (A-I) or (I), or any variation thereof, e.g., a compound offormula (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a),(V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or acompound selected from Compound Nos. 1-56 in Table 1 or Compound Nos.57-76 in Table 1-A, or a pharmaceutically acceptable salt thereof, in anamount effective to treat cancer in the individual. In some embodiments,the cancer is dependent upon activation of one or both of TLR8 and TLR9.In some embodiments, the cancer is activated B cell type-diffuse large Bcell lymphoma. In other embodiments, the cancer is Waldenstrom'smacroglobulinemia. In some embodiments, the cancer is hepatocellularcarcinoma (HCC). In some embodiments, cells of the cancer possess anoncogenic mutation in a myeloid differentiation primary response gene 88(MYD88). In a subset of the embodiments, the oncogenic mutation isselected from the group consisting of L265P, M232T, P258L, and Q143E.

The methods provided herein are suitable for prophylactic treatment,therapeutic treatment, or both. Prophylactic treatment refers totreatment that is initiated prior to observation of symptoms and/or asuspected exposure to a causative agent (e.g., a pathogen or carcinogen)of a condition. Generally, prophylactic treatment may reduce (a) thelikelihood that an individual receiving the treatment develops thecondition and/or (b) the duration and/or severity of symptoms in theevent the subject develops the condition. As used herein, therapeutictreatment refers to treatment initiated after observation of symptomsand/or a suspected exposure to a causative agent of the condition.Generally, therapeutic treatment may reduce the severity and/or durationof symptoms associated with the condition.

As demonstrated herein, compounds of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, inhibit TLR8-dependent and/orTLR9-dependent responses. In some embodiments, certain compounds offormula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV),(IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), orany variation thereof, or a pharmaceutically acceptable salt thereof, donot inhibit TLR1-dependent, TLR2-dependent, TLR3-dependent,TLR4-dependent, TLR5-dependent, TLR6-dependent, TLR7-dependent,TLR10-dependent, TLR11-dependent, TLR12-dependent and/or TLR13-dependentresponses. In some embodiments, certain compounds of formula (A-I), (I),(Ia), (To), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a),(VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variationthereof, or a pharmaceutically acceptable salt thereof, inhibit TLR8-and TLR9-dependent responses. In some embodiments, certain compounds offormula (A-I), (I), (Ia), (To), (I⁰a), (II), (IIa), (III), (IIIa), (IV),(IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), orany variation thereof, or a pharmaceutically acceptable salt thereof,inhibit TLR8- and/or TLR9-dependent responses, but not TLR7-dependentresponses. In some embodiments, the compound inhibits TLR8-dependentresponses, but not TLR7-dependent responses. In some embodiments, thecompound inhibits TLR9-dependent responses, but not TLR7-dependentresponses. In some embodiments, the compound inhibits TLR8- andTLR9-dependent responses, but not TLR7-dependent responses. In otherembodiments, certain compounds of formula (A-I), (I), (Ia), (To), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, inhibit TLR8-dependent but notTLR9-dependent responses. In other embodiments, certain compounds offormula (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV),(IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), orany variation thereof, or a pharmaceutically acceptable salt thereof,inhibit TLR9-dependent but not TLR8-dependent responses. In someembodiments, certain compounds of formula (A-I), (I), (Ia), (I⁰), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, inhibit TLR8-, TLR9- andTLR7-dependent responses. Inhibition of TLR-dependent responses can bedetermined in vitro, in vivo, and/or ex vivo.

The identification of compounds with dual TLR8 and TLR9 antagonistactivity without TLR7 antagonist activity is quite unexpected given theligand specificity of these receptors: single-stranded RNA for TLR8 asopposed to CpG-containing single-stranded DNA for TLR9. Given that bothTLR7 and TLR8 recognize similar single-stranded RNA structures and havethe highest degree of sequence homology among TLRs, it is alsounexpected that certain LTR8 inhibitors of the present disclosure do notinhibit TLR7.

Certain compounds of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa),(III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a),(VIII), (VIII-a), or any variation thereof, or a pharmaceuticallyacceptable salt thereof, that inhibit TLR8- and TLR9-dependent responsesinclude but are not limited to Compound Nos. 1, 2, 4, 33, 67, 19x, 51xand 54x.

Certain compounds of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa),(III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a),(VIII), (VIII-a), or any variation thereof, or a pharmaceuticallyacceptable salt thereof, that inhibit TLR9-dependent but notTLR8-dependent responses include but are not limited to Compound Nos. 5,22, 29, 43, 45, 45a, 45b, 46, 9x, 17x, 19x, 21x, 24x and 25x.

In some embodiments of any of the methods involving administration of acompound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III),(IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, to an individual (e.g., methods ofinhibiting an immune response, treating or preventing an immunologicaldisorder (e.g., autoimmune or inflammatory disease, etc.), the compoundof formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa),(IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, has a therapeutically acceptablesafety profile. The compound of formula (A-I), (I), (Ia), (To), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or any variation thereof, may forexample, have a therapeutically acceptable histological profileincluding an acceptably low, if any, toxicity of the liver, kidney,pancreas, or other organs. On occasion, small molecules have beenassociated with toxicity to certain organs such as the liver, kidney andpancreas. In some embodiments, the compound of formula (A-I), (I), (Ia),(To), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, hasa safety profile that is unexpected and advantageous. In someembodiments, a safety profile includes evaluation of toxicity, bloodchemistry, complete blood count, histological profile, and/or necrosis(e.g., liver, kidneys and/or heart). In some embodiments, the compoundof formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa),(IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, has a therapeutically acceptablelevel of toxicity. In some embodiments, the therapeutically acceptablesafety profile is determined in non-human primates, mice or rats.

In some embodiments of any of the methods involving administration of acompound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III),(IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, or a pharmaceutically acceptablesalt thereof, to an individual (e.g., methods of inhibiting an immuneresponse, treating or preventing an immunological disorder), thecompound has therapeutically acceptable pharmacokinetics (PK) or drugmetabolism and pharmacokinetics (DMPK). In some embodiments, thetherapeutically PK profile is determined in non-human primates, mice orrats.

In one aspect of the methods detailed herein, the methods describedexclude use of a compound of Table 1X. In another aspect, the methodsdescribed herein include the use of a compound of Table 1X. In someembodiments, the methods described herein include the use of a compoundlisted in Table 3.

B. Dosage and Mode of Administration

As with all compositions for inhibition of an immune response, theeffective amount and method of administration can vary based on theindividual, the condition to be treated and other factors evident to oneskilled in the art. For treatment of an individual, depending onactivity of the agent, manner of administration, purpose of theadministration (i.e., prophylactic or therapeutic), nature and severityof the disorder, age and body weight of the individual, different dosesmay be necessary. Dosages are generally selected by the physician orother health care professional in accordance with a variety ofparameters known in the art, such as severity of symptoms, history ofthe individual and the like. In some embodiments, an effective amount ofthe compound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa),(III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a),(VIII), (VIII-a), or any variation thereof, or a pharmaceuticallyacceptable salt thereof, is used in the methods described herein.

A suitable dosage range is one that provides the desired inhibition ofan immune response (e.g., suppression of tumor necrosis factor-alpha orother cytokine production in response to a TLR8 and/or TLR9 agonist).Generally, dosage is determined by the amount of the compoundadministered to the individual. An exemplary dosage range of thecompound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III),(IIIa), or any variation thereof, or a pharmaceutically acceptable saltthereof, in an amount to be delivered by subject weight is from about 1to 10000 mcg/kg. In some embodiments, the dosage is greater than about(lower limit) 1, 5, 10, 50, 100, 150, 200, 250, 300, 350, 400, 450 or500 mcg/kg. In some embodiments, the dosage is less than about (upperlimit) 10000, 7500, 5000, 2000, 1000, 900, 800, 700, 600, 500, 450, 400,350, 300, 250, 200, 150, or 100 mcg/kg. That is, the dosage is anywherein the range of from about 1 to 10000 mcg/kg in which the lower limit isless than the upper limit. An exemplary dosage range of the compound offormula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV),(IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), orany variation thereof, or a pharmaceutically acceptable salt thereof,given in amount to be delivered to a subject is from about 100 to 10000mcg. In some embodiments, the dosage is greater than about (lower limit)100, 500, 1000, 1500, 2000, 2500, 3000, 3500 or 4000 mcg. In someembodiments, the dosage is less than about (upper limit) 10000, 7500,5000, 4500, 4000, 3500, 3000, 2500, 2000, 1500, or 1000 mcg. That is,the dosage is anywhere in the range of from about 100 to 10000 mcg inwhich the lower limit is less than the upper limit. The absolute amountgiven to each individual depends on pharmacological properties such asbioavailability, clearance rate and route of administration.

A suitable dosing regimen is one that provides the desired effect in aprophylactic or therapeutic context. The number of doses administered bya chosen route may be one or more than one. Frequency of dosing mayrange from twice daily, daily, every other day, weekly, bi-weekly,monthly, bi-monthly, or 3 to 12 months between doses.

The pharmaceutical compositions comprising a compound of formula (A-I),(I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V),(V-a), (VI), (VI-a), (VII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, described herein may beadministered by systemic (e.g., parenteral or enteral) or local (e.g.,topical or intralesional injection) administration. In some embodiments,the pharmaceutical composition is administered orally, topically, or byinhalation. In some embodiments, the pharmaceutical composition isadministered parenterally. As described herein, tissues in whichunwanted immune activation is occurring or is likely to occur arepreferred targets for the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof. Thus, administration of thecompound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III),(IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, or a pharmaceutically acceptablesalt thereof, to lymph nodes, spleen, bone marrow, or blood may bedesired.

In some embodiments, the pharmaceutical composition comprising acompound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III),(IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, or a pharmaceutically acceptablesalt thereof, is administered parenterally. Parenteral routes ofadministration include, but are not limited to, transdermal,transmucosal, nasopharyngeal, pulmonary and direct injection. Parenteraladministration by injection may be by any parenteral injection route,including, but not limited to, intravenous (IV), including bolus andinfusion (e.g., fast or slow), intraperitoneal (IP), intramuscular (IM),subcutaneous (SC) and intradermal (ID) routes. Transdermal andtransmucosal administration may be accomplished by, for example,inclusion of a carrier (e.g., dimethylsulfoxide), by application ofelectrical impulses (e.g., iontophoresis) or a combination thereof.Compounds of the present disclosure suitable for parenteraladministration are generally formulated in United States Pharmacopeia(USP) grade water (e.g., water for injection) and may further comprisepH buffers, salts, bulking agents, preservatives, and otherpharmaceutically acceptable excipients. Compounds of the presentdisclosure for parenteral injection may be formulated inpharmaceutically acceptable sterile isotonic solutions such as salineand phosphate buffered saline for injection.

C. Combination Therapy

The compounds of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa),(III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a),(VIII), (VIII-a), or any variation thereof, or a pharmaceuticallyacceptable salt thereof, of the present disclosure can be administeredin combination with a second therapeutic agent (e.g., one or moreadditional therapeutic agents). Specifically, the methods describedherein may be practiced in combination with other therapies that make upthe standard of care for the disorder. In some embodiments, the secondtherapeutic agent is selected from the group consisting of anonsteroidal anti-inflammatory drug, a corticosteroid, an antimalarialdrug, an immunosuppressive drug, and a biologic. In specificembodiments, the second therapeutic agent is selected from the groupconsisting of cyclosporine, tacrolimus, prednisolone, hydrocortisone,sirolimus, everolimus, azathioprine, mycophenolic acid, methotrexate,basiliximab, daclizumab, teplizumab, telixizumab, dactinomycin,rituximab, anti-thymocyte globulin, and a combination thereof. Thecompound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III),(IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, or a pharmaceutically acceptablesalt thereof, may be administered simultaneously with one or moreadditional therapeutic agents (simultaneous administration).Alternatively, the compound of formula (A-I), (I), (Ia), (I⁰), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, may be administeredsequentially with one or more additional therapeutic agents (sequentialadministration). In some embodiments, sequential administration includesadministering the compound of formula (A-I), (I), (Ia), (I⁰), (I⁰a),(II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a),(VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, and the one or more additionaltherapeutic agents within about any of one minutes, five minutes, 30minutes, one hour, five hours, 24 hours, 48 hours, or a week from eachother. In some embodiments, the compound of formula (A-I), (I), (Ia),(I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, is administered by the sameroute of administration as the one or more additional therapeuticagents. In some embodiments, the compound of formula (A-I), (I), (Ia),(I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, is administered by a differentroute of administration than the one or more additional therapeuticagents.

In some embodiments, a compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, is administered in combinationwith a corticosteroid. In some embodiments, the corticosteroid is aglucocorticosteroid. In some embodiments, the corticosteroid is amineralocorticoid. Corticosteroids include, but are not limited to,corticosterone and derivatives, prodrugs, isomers and analogs thereof,cortisone and derivatives, prodrugs, isomers and analogs thereof,aldosterone and derivatives, prodrugs, isomers and analogs thereof,dexamethasone and derivatives, prodrugs, isomers and analogs thereof,prednisone and derivatives, prodrugs, isomers and analogs thereof,fludrocortisone and derivatives, prodrugs, isomers and analogs thereof,hydrocortisone and derivatives, prodrugs, isomers and analogs thereof,hydroxycortisone and derivatives, prodrugs, isomers and analogs thereof,betamethasone and derivatives, prodrugs, isomers and analogs thereof,budesonide and derivatives, prodrugs, isomers and analogs thereof,methylprednisolone and derivatives, prodrugs, isomers and analogsthereof, prednisolone and derivatives, prodrugs, isomers and analogsthereof, triamcinolone and derivatives, prodrugs, isomers and analogsthereof, and the like. In some embodiments, the corticosteroid isfludrocortisone or a derivative, prodrug, isomer or analog thereof. Insome embodiments, the corticosteroid is fludrocortisone. In someembodiments, the corticosteroid is hydroxycortisone or a derivative,prodrug, isomer or analog thereof. In some embodiments, thecorticosteroid is hydroxycortisone.

In some preferred embodiments, the combination of a compound of formula(A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIIa), (III), (IIIa), (IV),(IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), orany variation thereof, or a pharmaceutically acceptable salt thereof,with one or more additional therapeutic agents reduces the effectiveamount (including, but not limited to, dosage volume, dosageconcentration, and/or total drug dose administered) of the compound offormula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIIa), (III), (IIIa),(IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, or a pharmaceutically acceptablesalt thereof, and/or the one or more additional therapeutic agentsadministered to achieve the same result as compared to the effectiveamount administered when the compound of formula (A-I), (I), (Ia), (I⁰),(I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, or the additional therapeuticagent is administered alone. In some embodiments, the combination of acompound of formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIIa), (III),(IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, or a pharmaceutically acceptablesalt thereof, with the additional therapeutic agents reduces thefrequency of administrations of the additional therapeutic agentcompared to administration of the additional therapeutic agent alone. Insome embodiments, the combination of a compound of formula (A-I), (I),(Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a),(VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variationthereof, or a pharmaceutically acceptable salt thereof, with theadditional therapeutic agent reduces the total duration of treatmentcompared to administration of the additional therapeutic agent alone. Insome embodiments, the combination of an effective amount of the compoundof formula (A-I), (I), (Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa),(IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII), (VII-a), (VIII),(VIII-a), or any variation thereof, or a pharmaceutically acceptablesalt thereof, with the additional therapeutic agent is more efficaciouscompared to an effective amount of the compound of formula (A-I), (I),(Ia), (I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a),(VI), (VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variationthereof, or a pharmaceutically acceptable salt thereof, or theadditional therapeutic agent alone. In certain embodiments, theadditional therapeutic agent is a corticosteroid. Thus in someembodiments, the combination of a compound of formula (A-I), (I), (Ia),(I⁰), (I⁰a), (II), (IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI),(VI-a), (VII), (VII-a), (VIII), (VIII-a), or any variation thereof, or apharmaceutically acceptable salt thereof, with a corticosteroid reducesthe effective amount of corticosteroid administered as compared to thecorticosteroid administered alone.

In one aspect, provided is a compound of formula (A-I) or (I), or anyvariation thereof, e.g., a compound of formula (Ia), (I⁰), (I⁰a), (II),(IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII),(VII-a), (VIII), (VIII-a), or a compound selected from Compound Nos.1-56 in Table 1 or Compound Nos. 57-76 in Table 1-A, or apharmaceutically acceptable salt thereof, for use according to a methoddescribed herein, such as a method of inhibiting immune responsedetailed herein, or a method of treating an immunological disorder,inflammatory disorder, or cancer detailed herein.

Also provided is use of a compound of formula (A-I) or (I), or anyvariation thereof, e.g., a compound of formula (Ia), (I⁰), (I⁰a), (II),(IIa), (III), (IIIa), (IV), (IV-a), (V), (V-a), (VI), (VI-a), (VII),(VII-a), (VIII), (VIII-a), or a compound selected from Compound Nos.1-56 in Table 1 or Compound Nos. 57-76 in Table 1-A, or apharmaceutically acceptable salt thereof, in the manufacture of amedicament for inhibiting immune response detailed herein, or for thetreatment of an immunological disorder, inflammatory disorder, or cancerdetailed herein.

Kits

The invention further provides kits for carrying out the methods of theinvention, which comprises one or more compounds described herein or apharmacological composition comprising a compound described herein. Thekits may employ any of the compounds disclosed herein. In one variation,the kit employs a compound described herein or a pharmaceuticallyacceptable salt thereof. The kits may be used for any one or more of theuses described herein, and, accordingly, may contain instructions foruse according to a method detailed herein, such as a method of forinhibiting immune response, or a method of treating an immunologicaldisorder or cancer.

Kits generally comprise suitable packaging. The kits may comprise one ormore containers comprising any compound described herein. Each component(if there is more than one component) can be packaged in separatecontainers or some components can be combined in one container wherecross-reactivity and shelf life permit. One or more components of a kitmay be sterile and/or may be contained within sterile packaging.

The kits may be in unit dosage forms, bulk packages (e.g., multi-dosepackages) or sub-unit doses. For example, kits may be provided thatcontain sufficient dosages of a compound as disclosed herein (e.g., atherapeutically effective amount) and/or a second pharmaceuticallyactive compound useful for a disease detailed herein to provideeffective treatment of an individual for an extended period, such as anyof a week, 2 weeks, 3 weeks, 4 weeks, 6 weeks, 8 weeks, 3 months, 4months, 5 months, 7 months, 8 months, 9 months, or more. Kits may alsoinclude multiple unit doses of the compounds and instructions for useand be packaged in quantities sufficient for storage and use inpharmacies (e.g., hospital pharmacies and compounding pharmacies).

The kits may optionally include a set of instructions, generally writteninstructions, although electronic storage media (e.g., magnetic disketteor optical disk) containing instructions are also acceptable, relatingto the use of component(s) of the methods of the present invention. Theinstructions included with the kit generally include information as tothe components and their administration to an individual.

SYNTHETIC EXAMPLES

The chemical reactions in the Synthetic Examples described can bereadily adapted to prepare a number of other compounds of the invention,and alternative methods for preparing the compounds of this inventionare deemed to be within the scope of this invention. For example, thesynthesis of non-exemplified compounds according to the invention can besuccessfully performed by modifications apparent to those skilled in theart, e.g., by appropriately protecting interfering groups, by utilizingother suitable reagents known in the art other than those described, orby making routine modifications of reaction conditions. Alternatively,other reactions disclosed herein or known in the art will be recognizedas having applicability for preparing other compounds of the invention.

Abbreviations used in the description of the chemistry and in theExamples that follow are: EDCI(1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride); MgCl₂(magnesium chloride); Et₂O (diethyl ether); DCM (dichloromethane); DMF(dimethylformamide); DMSO (dimethyl sulfoxide); EtOAc ethyl acetate);EtOH (ethanol); MeCN (acetonitrile); MeOH (methanol); POCl₃ (phosphoryltrichloride); NaHCO₃ (sodium bicarbonate); MS (mass spectrometry); NMR(nuclear magnetic resonance); RT (room temperature); sat. aq. (saturatedaqueous); THF (tetrahydrofuran); TLC (thin layer chromatography); TEA(triethylamine); HATU(2-(3H-[1,2,3]triazolo[4,5-b]pyridin-3-yl)-1,1,3,3-tetramethyl-isouroniumhexafluorophosphate); HOBt (1-hydroxybenzotriazole); TFA(trifluoroacetic acid); DMAP (N,N-dimethylpyridin-4-amine).

Example 1 Synthesis of Compound No. 1N-(3-(benzyl(methyl)amino)propyl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide

Step 1.1: Synthesis of 4-acetyl-5-methylfuran-2,3-dione (1.1)

To a solution of pentane-2,4-dione (20 g, 0.2 mol) and oxalyl dichloride(26.7 g, 0.206 mol) in Et₂O (500 mL) was added MgCl₂ (1.90 g, 20 mmol)at RT. It was stirred at the same temperature for 2 h. Then the reactionmixture was concentrated to provide 1.1 (29.2 g, 94.8% yield) as yellowoil, which was used directly for next step.

Step 1.2: Synthesis of4-acetyl-5-methyl-1-p-tolyl-1H-pyrazole-3-carboxylic acid (1.2)

To a solution of 1.1 (29.2 g, 0.19 mol) in toluene (200 mL) was addedp-tolylhydrazine (15.8 g, 0.10 mol) at RT, the mixture was then stirredat 60° C. overnight. Solvent was removed under reduced pressure. Thecrude product was purified on column chromatography on silica gel(DCM/MeOH=10/1) to get 1.2 (20 g, 40.8% yield) as a yellow solid. LCMS(ESI+) m/z=259.1 (M+H).

Step 1.3: Synthesis of3,4-dimethyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazin-7(6H)-one (1.3)

To a solution of 1.2 (20.0 g, 77.5 mmol) in EtOH (200 mL) was addedhydrazine hydrate (19.3 g, 387 mmol) at RT. The reaction mixture wasthen stirred at 100° C. for 4 h. After that the mixture was cooled to RTand the precipitate was collected by filtration to get 1.3 (15 g, 76.2%yield) as a white solid. LCMS (ESI+) m/z=255.2 (M+H).

Step 1.4: Synthesis of7-chloro-3,4-dimethyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazine (1.4)

To a solution of 1.3 (7.50 g, 29.5 mmol) in MeCN (3 mL) was added POCl₃(13.4 g, 88.5 mmol) at RT. The reaction mixture was then stirred refluxfor 2 h. Upon completion, the mixture was concentrated in vacuo and theresidue was poured into ice-water. Then its pH was adjusted to 8 withsat. aq. NaHCO₃ solution, the aqueous layer was extracted with DCM (70mL×3). The combined organic layers were washed successively with water(70 mL), brine (70 mL) and then dried over Na₂SO₄, filtered and thefiltrate was concentrated to afford 1.4 (7.6 g, 94.7% yield) as brownoil. LCMS (ESI+) m/z=273.1 (M+H).

Step 1.5: Synthesis of ethyl1-(3,4-dimethyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazin-7-yl)piperidine-4-carboxylate(1.5)

To a solution of 1.4 (7.60 g, 28 mmol) and ethylpiperidine-4-carboxylate (6.50 g, 42 mmol) in EtOH (50 mL) was added TEA(8.40 g, 84 mmol) at RT. The reaction mixture was stirred reflux for 2h. Upon completion, solvent was removed under reduced pressure, theresidue was diluted with water and extracted with DCM (50 mL×3). Thecombined organic layers were washed with brine, dried over Na₂SO₄,filtered and concentrated to afford 1.5 (5.3 g, 48.1% yield). ¹H NMR(400 MHz, CDCl₃) δ 7.40-7.35 (m, 4H), 5.06 (dt, J=13.3, 3.1 Hz, 2H),4.13 (q, J=7.1 Hz, 2H), 3.26-3.19 (m, 2H), 2.76 (s, 3H), 2.69 (s, 3H),2.60 (tt, J=11.0, 3.9 Hz, 1H), 2.47 (s, 3H), 2.05-1.98 (m, 2H), 1.86(ddd, J=13.6, 11.4, 5.7 Hz, 2H), 1.25 (t, J=7.1 Hz, 3H). LCMS (ESI+)m/z=394.2 (M+H).

Step 1.6: Synthesis of1-(3,4-dimethyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazin-7-yl)piperidine-4-carboxylic acid (1.6)

To a solution of 1.5 (5.30 g, 13 mmol) in MeOH (20 mL) was added IN aq.LiOH solution (20 mL) dropwise. The reaction mixture was then stirred atRT for 2 h. MeOH was removed in vacuo and the aqueous layer was adjustedto pH=6 with IN aq. HCl solution, the formed solid was collected byfiltration to get 1.6 (3 g, 63.2% yield) as a white solid. LCMS (ESI+)m/z=366.1 (M+H).

Step 1.7: Synthesis ofN-(3-(benzyl(methyl)amino)propyl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(1)

To a solution of 1.6 (100 mg, 0.274 mmol),N¹-benzyl-N¹-methylpropane-1,3-diamine (73 mg, 0.411 mmol), HOBt (74 mg,0.548 mmol) and TEA (83 mg, 0.822 mmol) in DCM (4 mL) was added EDCI(105 mg, 0.548 mmol) portion wise under ice-water bath. The reactionmixture was then stirred at RT for 16 h. Upon completion, the reactionmass was diluted with DCM (30 mL) and washed with water (25 mL) andbrine (25 mL). The organic layer was dried over Na₂SO₄ and concentratedin vacuo. The crude product was purified on prep-HPLC and lyophilized toafford 1 (38 mg, 26.4% yield) as white solid. ¹H NMR (400 MHz, CDCl₃) δ7.37 (t, J=9.2 Hz, 4H), 7.32-7.28 (m, 4H), 7.23-7.18 (m, 1H), 6.79 (br,1H), 5.18 (d, J=13.2 Hz, 2H), 3.47 (s, 2H), 3.32 (q, J=5.2 Hz, 2H),3.07-3.00 (m, 2H), 2.76 (s, 3H), 2.69 (s, 3H), 2.47 (s, 3H), 2.45 (t,J=6.4 Hz, 2H), 2.29-2.23 (m, 1H), 2.22 (s, 3H), 1.86-1.74 (m, 4H),1.69-1.64 (m, 2H). LCMS (ESI+) m/z=263.8 (M/2+H).

Example 2 Synthesis of Compound Nos. 2, 3, 4, 5, 7, 8, 9, 13, 15, 17,18, 22, 31, 32, 2-1, 2-2, 2-3, 2-4, 2-5, 2-6, 2-12, and 21x

LCMS Compound ¹H NMR (400 MHz) m/z No. R^(E) (Solvent) δ ppm (M + H)  2

(CDCl₃) 7.39-7.34 (m, 4H), 7.33-7.27 (m, 5H), 5.21 (d, J = 13.2 Hz, 2H),3.64-3.62 (m, 2H), 3.56-3.53 (m, 2H), 3.52 (s, 2H), 3.08 (td, J = 13.1,2.4 Hz, 2H), 2.79-2.72 (m, 4H), 2.68 (s, 3H), 2.53-2.41 (m, 7H), 2.01-1.91 (m, 2H), 1.81-1.77 (m, 2H). 524  3

(DMSO-d6) δ 8.22 (d, J = 7.5 Hz, 1H), 7.51 (d, J = 8.3 Hz, 2H), 7.44 (d,J = 8.3 Hz, 2H), 5.01 (d, J = 12.9 Hz, 2H), 4.22-4.13 (m, 1H), 3.45 (t,J = 7.2 Hz, 2H), 3.01 (td, J = 12.8, 2.0 Hz, 2H), 2.77-2.73 (m, 2H),2.67 (s, 3H), 2.66 (s, 3H), 2.45-2.38 (m, 4H), 2.19 (s, 3H), 1.72 (dd, J= 12.8, 3.1 Hz, 2H), 1.59 (ddd, J = 16.0, 12.7, 4.0 Hz, 2H). 434  4

(CDCl₃) 7.39-7.34 (m, 4H), 7.33-7.29 (m, 2H), 7.25-7.23 (m, 3H), 6.04(d, J = 7.8 Hz, 1H), 5.21 (d, J = 13.4 Hz, 2H), 4.59-4.51 (m, 1H),3.60-3.57 (m, 4H), 3.12-3.05 (m, 2H), 2.96-2.93 (m, 2H), 2.76 (s, 3H),2.69 (s, 3H), 2.47 (s, 3H), 2.44-2.36 (m, 1H), 1.93 (dd, J = 12.8, 2.5Hz, 2H), 1.88-1.81 (m, 2H). 510  5

(CD₃OD) 7.38-7.33 (m, 4H), 5.09 (d, J = 13.2 Hz, 2H), 3.11 (t, J = 6.9Hz, 2H), 3.04- 2.97 (m, 2H), 2.65 (s, 3H), 2.62 (s, 3H), 2.46-2.41 (m,1H), 2.39 (s, 3H), 2.27-2.24 (m, 2H), 2.15 (s, 6H), 1.79-1.67 (m, 4H),1.63-1.56 (m, 2H). 450  7

(CDCl₃) 7.39-7.34 (m, 4H), 5.20 (d, J = 13.2 Hz, 2H), 3.16 (d, J = 5.6Hz, 2H), 3.13-3.06 (m, 2H), 2.76 (s, 3H), 2.69 (s, 3H), 2.54 (s, 2H),2.47 (s, 2H), 2.45-2.39 (m, 1H), 1.98 (dd, J = 13.0, 2.8 Hz, 2H), 1.83(ddd, J = 24.9, 12.4, 4.0 Hz, 2H), 0.87 (s, 6H). 450  8

(CDCl₃) 7.38-7.34 (m, 4H), 6.30 (s, 1H), 5.19 (d, J = 13.3 Hz, 2H), 3.31(dd, J = 11.4, 5.6 Hz, 2H), 3.12-3.05 (m, 2H), 2.81-2.70 (m, 6H), 2.68(s, 3H), 2.46 (s, 3H), 2.44-2.38 (m, 1H), 1.96-1.86 (m, 4H), 1.05 (s,3H), 1.03 (s, 3H). 450  9

(CDCl₃) 7.39-7.35 (m, 4H), 6.05 (s, 1H), 5.15 (d, J = 13.1 Hz, 2H), 3.32(dd, J = 11.3, 5.4 Hz, 2H), 3.01 (td, J = 13.0, 1.9 Hz, 2H), 2.75 (s,3H), 2.68 (s, 3H), 2.47 (s, 3H), 2.40 (t, J = 6.0 Hz, 2H), 2.23 (d, J =10.9 Hz, 8H), 1.78 (d, J = 12.1 Hz, 2H), 1.64-1.59 (m, 3H), 1.44-1.27(m, 2H). 464 13

(DMSO-d6) 8.03 (t, J = 5.5 Hz, 1H), 7.51- 7.49 (m, 2H), 7.43 (d, J = 8.2Hz, 2H), 4.12- 4.08 (m, 1H), 3.99 (s, 1H), 3.78 (ddd, J = 18.6, 10.4,7.3 Hz, 2H), 3.07 (dd, J = 12.7, 6.8 Hz, 2H), 3.04-2.98 (m, 1H), 2.65(s, 3H), 2.63 (s, 3H), 2.42 (s, 3H), 2.16 (dd, J = 14.3, 7.1 Hz, 2H),2.12-2.01 (m, 8H), 1.56-1.49 (m, 2H). 436 15

(DMSO-d6) 8.01 (t, J = 5.6 Hz, 1H), 7.50 (d, J = 8.3 Hz, 2H), 7.43 (d, J= 8.4 Hz, 2H), 4.37 (t, J = 8.5 Hz, 2H), 4.32-4.28 (m, 2H), 3.54-3.47(m, 1H), 3.08 (dd, J = 12.8, 6.8 Hz, 2H), 2.65 (s, 6H), 2.43 (s, 3H),2.17 (dd, J = 12.9, 5.7 Hz, 2H), 2.09 (s, 6H), 1.56-1.49 (m, 2H). 422 17

(CD₃OD) 7.47-7.42 (m, 4H), 5.18 (d, J = 13.2 Hz, 2H), 4.34-4.27 (m, 1H),3.12-3.05 (m, 2H), 2.81 (dd, J = 10.1, 7.3 Hz, 1H), 2.74 (s, 3H),2.71-2.67 (m, 4H), 2.55-2.49 (m, 2H), 2.48 (s, 3H), 2.41 (dd, J = 10.1,5.0 Hz, 1H), 2.35 (s, 3H), 2.30-2.21 (m, 1H), 1.84-1.75 (m, 4H),1.72-1.63 (m, 1H). 448 18

(CD₃OD) 7.47-7.42 (m, 4H), 5.18 (d, J = 13.2 Hz, 2H), 3.68-3.60 (m, 1H),3.14-3.05 (m, 2H), 2.85 (d, J = 11.9 Hz, 2H), 2.75 (s, 3H), 2.71 (s,3H), 2.55-2.49 (m, 1H), 2.48 (s, 3H), 2.27 (s, 3H), 2.13 (t, J = 11.6Hz, 2H), 1.87-1.79 (m, 6H), 1.57-1.47 (m, 2H). 462 22

(DMSO-d6) δ 7.78 (t, J = 5.5 Hz, 1H), 7.50 (d, J = 8.4 Hz, 2H), 7.43 (d,J = 8.2 Hz, 2H), 4.96 (d, J = 12.9 Hz, 2H), 3.06-2.96 (m, 4H), 2.66 (d,J = 1.5 Hz, 6H), 2.43 (s, 3H), 2.16 (t, J = 7.2 Hz, 2H), 2.08 (s, 6H),1.98 (s, 3H), 1.67 (d, J = 11.5 Hz, 2H), 1.53-1.46 (m, 2H), 1.26-1.15(m, 2H). 464 31

(DMSO-d6) 7.80 (t, J = 5.5 Hz, 1H), 7.51 (d, J = 8.3 Hz, 2H), 7.44 (d, J= 8.2 Hz, 2H), 5.01 (d, J = 13.0 Hz, 2H), 3.05-2.99 (m, 4H), 2.66 (d, J= 4.0 Hz, 6H), 2.46-2.38 (m, 4H), 2.21-2.17 (m, 2H), 2.11 (s, 6H),1.74-1.70 (m, 2H), 1.67-1.56 (m, 2H), 1.37 (t, J = 3.2 Hz, 4H). 464 32

(DMSO-d6) 7.77 (t, J = 5.6 Hz, 1H), 7.51 (d, J = 8.4 Hz, 2H), 7.44 (d, J= 8.1 Hz, 2H), 5.01 (d, J = 13.0 Hz, 2H), 3.04-2.98 (m, 4H), 2.66 (d, J= 3.9 Hz, 6H), 2.44-2.38 (m, 4H), 2.13 (t, J = 7.2 Hz, 2H), 2.07 (s,6H), 1.72 (dd, J = 12.7, 2.6 Hz, 2H), 1.61 (ddd, J = 15.9, 12.5, 3.8 Hz,2H), 1.41-1.32 (m, 4H), 1.25-1.18 (m, 2H). 478 2-1 

(CDCl₃) 7.37 (s, 4H), 7.15-7.11 (m, 2H), 6.66-6.62 (m, 3H), 5.88 (t, J =5.6 Hz, 1H), 5.20 (d, J = 13.2 Hz, 2H), 4.28 (br, 1H), 3.20 (d, J = 6.4Hz, 2H), 3.12-3.05 (m, 2H), 2.89 (s, 2H), 2.77 (s, 3H), 2.69 (s, 3H),2.47 (s, 3H), 2.45-2.38 (m, 1H), 1.95-1.77 (m, 4H), 0.95 (s, 6H). 5262-2 

(DMSO-d6) 7.74 (d, J = 4.5 Hz, 1H), 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J= 8.2 Hz, 2H), 5.01 (d, J = 13.1 Hz, 2H), 3.01 (td, J = 12.8, 1.9 Hz,2H), 2.66 (d, J = 4.2 Hz, 6H), 2.55 (d, J = 4.6 Hz, 3H), 2.43-2.37 (m,4H), 1.75- 1.71 (m, 2H), 1.61 (qd, J = 12.5, 3.8 Hz, 2H). 379 2-3 

(CD₃OD) 7.47-7.42 (m, 4H), 5.17 (d, J = 13.2 Hz, 2H), 3.68-3.63 (m, 6H),3.57 (d, J = 4.6 Hz, 2H), 3.19-3.12 (m, 2H), 3.06-2.99 (m, 1H), 2.74 (s,3H), 2.70 (s, 3H), 2.47 (s, 3H), 1.88-1.79 (m, 4H). 435 2-4 

(DMSO-d6) 7.87 (t, J = 5.5 Hz, 1H), 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J= 8.1 Hz, 2H), 7.00 (d, J = 6.7 Hz, 1H), 6.95 (t, J = 7.7 Hz, 1H),6.55-6.51 (m, 1H), 6.45 (d, J = 7.8 Hz, 1H), 5.02 (d, J = 13.1 Hz, 2H),3.25 (t, J = 8.3 Hz, 2H), 3.12 (dd, J = 12.5, 6.7 Hz, 2H), 3.06-2.99 (m,4H), 2.85 (t, J = 8.3 Hz, 2H), 2.67 (s, 3H), 2.66 (s, 3H), 2.46-2.43 (m,4H), 1.75 (d, J = 10.3 Hz, 2H), 1.69-1.58 (m, 4H). 524 2-5 

(CD₃OD) 7.46-7.41 (m, 4H), 6.93-6.88 (m, 1H), 6.82 (d, J = 6.9 Hz, 1H),6.56-6.51 (m, 1H), 6.46-6.42 (m, 1H), 5.17 (d, J = 13.2 Hz, 2H),3.29-3.21 (m, 6H), 3.12-3.05 (m, 2H), 2.73 (s, 3H), 2.69-2.66 (m, 5H),2.56-2.48 (m, 1H), 2.47 (s, 3H), 1.93-1.73 (m, 8H). 538 2-6 

(CD₃OD) 7.47-7.41 (m, 4H), 7.26-7.22 (m, 2H), 7.18-7.11 (m, 3H), 5.17(d, J = 13.2 Hz, 2H), 3.18 (t, J = 7.1 Hz, 2H), 3.12-3.05 (m, 2H), 2.73(s, 3H), 2.70 (s, 3H), 2.62 (t, J = 7.6 Hz, 2H), 2.55-2.50 (m, 1H), 2.47(s, 3H), 1.85-1.76 (m, 6H). 483 2-12

(DMSO-d6) 7.75 (t, J = 5.6 Hz, 1H), 7.51 (d, J = 8.4 Hz, 2H), 7.43 (d, J= 8.2 Hz, 2H), 7.26-7.21 (m, 2H), 7.17-7.10 (m, 3H), 5.01 (d, J = 13.0Hz, 2H), 3.03-2.98 (m, 4H), 2.67 (s, 3H), 2.66 (s, 3H), 2.54 (t, J = 7.6Hz, 2H), 2.43 (s, 3H), 2.41-2.36 (m, 1H), 1.71-1.50 (m, 6H), 1.44-1.36(m, 2H), 1.28-1.20 (m, 2H). 511 21x

(DMSO-d6) 7.72 (t, J = 5.5 Hz, 1H), 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J= 8.3 Hz, 2H), 5.00 (d, J = 13.0 Hz, 2H), 3.11 (dd, J = 12.6, 6.6 Hz,2H), 3.01 (t, J = 11.6 Hz, 2H), 2.66 (d, J = 4.0 Hz, 6H), 2.46-2.39 (m,4H), 2.28- 2.20 (m, 2H), 2.12 (s, 6H), 1.72 (d, J = 10.3 Hz, 2H), 1.60(qd, J = 12.5, 3.6 Hz, 2H). 436

Compound Nos. 6, 11, 33, and 12a were prepared using the appropriatestarting materials and reagents according to the same procedures as inExample 1.

Example 3 Synthesis of Compound No. 6N-(3-(1H-imidazol-4-yl)propyl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide

Step 6.1: Synthesis of1-(3,4-dimethyl-2-p-tolyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(1-trityl-1H-imidazol-4-yl)propyl)piperidine-4-carboxamide(6.1)

To a solution of 1.6 (100 mg, 0.274 mmol) in DMF (2 mL) were added3-(1-trityl-1H-imidazol-4-yl)propan-1-amine (151 mg, 0.411 mmol), TEA(83 mg, 0.822 mmol) and HATU (135 mg, 0.356 mmol) successively at RT.The mixture was then stirred at the same temperature for 16 h. Uponcompletion, the reaction mixture was poured into water (20 mL) andextracted with EtOAc (15 mL×3). The combined organic layers were washedwith water (20 mL×2), brine (20 mL), dried over Na₂SO₄ and concentratedin vacuo. The residue was purified on column chromatography on silicagel (DCM/MeOH=15/1) to give 6.1 (150 mg, 76.7% yield) as white solid.LCMS (ESI+) m/z=715 (M+H).

Step 6.2: Synthesis ofN-(3-(1H-imidazol-4-yl)propyl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(6)

To a solution of 6.1 (150 mg, 0.210 mmol) in DCM (3 mL) was added TFA (3mL) dropwise under ice-water bath. The resulting mixture was stirred atRT for 2 h. Upon completion, sat. aq. NaHCO₃ solution was added toadjust pH to 8. The aqueous layer was extracted with DCM (20 mL×3). Thecombined organic layers were dried over Na₂SO₄ and concentrated invacuo. The crude product was purified on prep-HPLC and lyophilized toafford 6 (9 mg, 9.1% yield) as white solid. ¹H NMR (400 MHz, CDCl₃)δ7.48 (s, 1H), 7.37 (s, 4H), 6.76 (s, 1H), 6.18 (br, 1H), 5.19 (d,J=13.6 Hz, 2H), 7.32-7.28 (m, 4H), 7.23-7.18 (m, 1H), 6.79 (br, 1H),5.18 (d, J=13.2 Hz, 2H), 3.35 (q, J=6.0 Hz, 2H), 3.14-3.07 (m, 2H), 2.77(s, 3H), 2.70 (s, 3H), 2.61 (t, J=6.0 Hz, 2H), 2.50-2.43 (m, 4H),1.93-1.78 (m, 6H). LCMS (ESI+) m/z=473.4 (M+H).

Example 4 Synthesis of Compound No. 11N-(3-(azetidin-1-yl)propyl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide

Synthesis ofN-(3-(azetidin-1-yl)propyl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(11)

To a solution of 1.6 (200 mg, 0.548 mmol), 3-bromopropan-1-aminehydrobromide (144 mg, 0.658 mmol), TEA (83 mg, 0.822 mmol) and DMAP (80mg, 0.658 mmol) in DCM (9 mL) was added EDCI (115 mg, 0.603 mmol)portion wise under ice-water bath. The resulting mixture was stirred atRT for 3 h. Then TEA (110 mg, 1.096 mmol) and azetidine (312 mg, 5.48mmol) were added successively under ice-water bath. The reaction mixturewas stirred at RT for further 16 h. The reaction mass was then dilutedwith DCM (40 mL) and washed with water (30 mL) and brine (30 mL). Theorganic layer was dried over Na₂SO₄ and concentrated in vacuo. The crudeproduct was purified by prep-HPLC and lyophilized to afford 11 (35 mg,13.9% yield) as white solid. ¹H NMR (400 MHz, CD₃OD) δ 7.49-7.44 (m,4H), 5.19 (d, J=13.2 Hz, 2H), 3.25 (t, J=7.2 Hz, 4H), 3.18 (t, J=6.8 Hz,2H), 3.14-3.07 (m, 2H), 2.76 (s, 3H), 2.73 (s, 3H), 2.56-2.52 (m, 2H),2.50 (s, 3H), 2.47 (t, J=8.0 Hz, 2H), 2.14-2.07 (m, 2H), 1.88-1.77 (m,4H), 1.58-1.50 (m, 2H). LCMS (ESI+) m/z=462.4 (M+H).

Example 5 Synthesis of Compound No. 19x1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-morpholinopropyl)piperidine-4-carboxamide

Compound No. 19x was prepared using the appropriate starting materialsand reagents according to the same procedures as in Example 4. ¹H NMR(400 MHz, DMSO-d6) δ 7.80 (t, J=5.6 Hz, 1H), 7.51 (d, J=8.4 Hz, 2H),7.44 (d, J=8.1 Hz, 2H), 5.01 (d, J=13.1 Hz, 2H), 3.54 (t, J=4.6 Hz, 4H),3.07-2.98 (m, 4H), 2.66 (d, J=4.0 Hz, 6H), 2.45-2.38 (m, 4H), 2.30 (br,4H), 2.24 (t, J=7.2 Hz, 2H), 1.72 (dd, J=12.8, 2.6 Hz, 2H), 1.66-1.59(m, 2H), 1.56-1.49 (m, 2H). LCMS m/z=492 (M+H).

Example 6 Synthesis of Compound No. 12a1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-((1r,3r)-3-(dimethylamino)cyclobutyl)piperidine-4-carboxamide

Step 12a.1: Synthesis of tert-butyl(1r,3r)-3-(1-(3,4-dimethyl-2-p-tolyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamido)cyclobutylcarbamate(12a.1)

To a solution of 1.6 (200 mg, 0.548 mmol), tert-butyl(1r,3r)-3-aminocyclobutylcarbamate (122 mg, 0.658 mmol), HOBt (248 mg,1.096 mmol) and TEA (166 mg, 1.644 mmol) in DCM (10 mL) was added EDCI(210 mg, 1.096 mmol) portion wise under ice-water bath. The reactionmixture was then stirred at RT for 16 h. Upon completion, the reactionmass was diluted with DCM (50 mL) and washed with water (30 mL) andbrine (30 mL). The organic layer was dried over Na₂SO₄ and concentratedin vacuo. The crude product was purified on prep-TLC using 9% MeOH/DCMto afford 12a.1 (190 mg, 65.0% yield) as white solid. LCMS (ESI+)m/z=534 (M+H).

Step 12a.2: Synthesis ofN-((1r,3r)-3-aminocyclobutyl)-1-(3,4-dimethyl-2-p-tolyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(12a.2)

To a solution of 12a.1 (190 mg, 0.356 mmol) in MeOH (7 mL) was added 4MHCl in 1,4-dioxane (7 mL) dropwise. The mixture was stirred at RT for 2h. Upon completion, the solvent was removed in vacuo, the residue wasdissolved in water, sat. aq. NaHCO₃ solution was then added to adjust pHto 8. The aqueous layer was extracted with 10% MeOH/DCM (20 mL×3). Thecombined organic layers were washed with brine (30 mL), dried overNa₂SO₄ and concentrated in vacuo to give 12a.2 (120 mg, 77.8% yield) aspale yellow solid. LCMS (ESI+) m/z=434 (M+H).

Step 12a.3: Synthesis of1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-((1r,3r)-3-(dimethylamino)cyclobutyl)piperidine-4-carboxamide(12a)

To a solution of 12a.2 (120 mg, 0.277 mmol) in MeOH (6 mL) were added37% aq. HCHO (4 mL) and a catalytic amount of AcOH. The resultingmixture was stirred at RT for 1 h. After that NaBH₃CN (70 mg, 1.108mmol) was added portion wise under ice-water bath. The reaction mixturewas stirred at RT for further 3 h. The mixture was then partitionedbetween DCM (40 mL) and water (30 mL), and organic layer was separated,washed with brine (20 mL) and dried over Na₂SO₄. The solvent was removedin vacuo, the residue was purified on prep-HPLC and lyophilized toafford 12a (64 mg, 50.1% yield) as white solid. ¹H NMR (400 MHz, CD₃OD)δ 7.48-7.43 (m, 4H), 5.19 (d, J=13.2 Hz, 2H), 4.22-4.16 (m, 1H),3.14-3.07 (m, 2H), 2.96-2.89 (m, 1H), 2.75 (s, 3H), 2.72 (s, 3H),2.59-2.52 (m, 1H), 2.49 (s, 3H), 2.34-2.27 (m, 2H), 2.17 (s, 6H),2.13-2.06 (m, 2H), 1.86-1.77 (m, 4H). LCMS (ESI+) m/z=462.4 (M+H).

Example 7 Synthesis of Compound No. 29N-(3-(dimethylamino)propyl)-1-(2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide

Step 29.1: Synthesis of tert-butyl4-(3-(dimethylamino)propylcarbamoyl)piperidine-1-carboxylate (29.1)

To a solution of 1-(tert-butoxycarbonyl)piperidine-4-carboxylic acid(10.0 g, 0.044 mol), N¹,N¹-dimethylpropane-1,3-diamine (8.91 g, 0.087mol), HOBt (8.84 g, 0.066 mol) and TEA (13.2 g, 0.131 mol) in DCM (100mL) was added EDCI (10.9 g, 0.057 mol) portion wise under ice-waterbath. The reaction mixture was then stirred at RT for 16 h. Uponcompletion, the reaction mass was diluted with 10% MeOH/DCM (150 mL) andwashed with water (100 mL) and brine (100 mL). The organic layer wasdried over Na₂SO₄ and concentrated in vacuo. The residue was purified oncolumn chromatography on silica gel (DCM/MeOH=15/1) to afford 29.1 (8.40g, 61.5% yield) as yellow oil. LCMS (ESI+) m/z=314.2 (M+H).

Step 29.2: Synthesis ofN-(3-(dimethylamino)propyl)piperidine-4-carboxamide (29.2)

To a solution of 29.1 (8.40 g, 0.027 mol) in MeOH (35 mL) was added 4MHCl in 1,4-dioxane (33.5 mL) dropwise under ice-water bath. The mixturewas stirred at RT for 2 h. Upon completion, the solvent was removed invacuo, the residue was dissolved in water, sat. aq. NaHCO₃ solution wasthen added to adjust pH to 8. The solvent was removed in vacuo, theresidue was triturated with MeOH, filtered and the filtrate wasconcentrated in vacuo and lyophilized to afford 29.2 (4.60 g, 80.7%yield) as yellow solid. LCMS (ESI+) m/z=214 (M+H).

Step 29.3: Synthesis of 4-methylbenzenediazonium tetrafluoroborate(29.3)

To a stirred solution of BF₃-etherate (38 mL, 0.299 mol) in DCM (120 mL)under argon atmosphere was added a solution of p-toluidine (20.0 g,0.187 mol) in DCM (240 mL) dropwise under ice-salt bath, followed by theaddition of a solution of tert-butyl nitrite (23.2 g, 0.224 mol) in DCM(120 mL) dropwise over a 10 min period. After stirred under ice-saltbath for 10 min, the reaction mixture was placed in an ice-water bathfor another 1 h. The suspension was then diluted with hexane. Theprecipitate was filtered and washed with hexane and then diethyl ether.The solid was collected and dried under high vacuum to afford 29.3 (17.0g) as brown solid which was stored in a −10° C. freezer.

Step 29.4: Synthesis of ethyl 2-(2-p-tolylhydrazono)propanoate (29.4)

A solution of ethyl 2-methyl-3-oxobutanoate (11.9 g, 0.083 mol) andsodium acetate trihydrate (16.9 g, 0.124 mol) in EtOH (220 mL) wascooled in an ice bath. To the solution, while being stirred, 29.3 (17.0g, 0.083 mol) was added slowly. The reaction mixture was stirred at 0°C. for 4 h. The EtOH was evaporated to half-volume, and the mixture waspoured into 400 g of ice-water mixture. The precipitate was collectedand triturated with EtOH. The resulting solid was collected byfiltration and dried in vacuo to give 29.4 (3.00 g, 16.4% yield) asbrown solid. ¹H NMR (400 MHz, CDCl₃) δ 7.66 (br, 1H), 7.10 (s, 4H), 4.31(q, J=7.2 Hz, 2H), 2.30 (s, 3H), 2.09 (s, 3H), 1.38 (t, J=7.2 Hz, 3H).LCMS (ESI+) m/z=221.3 (M+H).

Step 29.5: Synthesis of ethyl4-formyl-1-p-tolyl-1H-pyrazole-3-carboxylate (29.5)

POCl₃ (6.26 g, 40.9 mmol) was added to DMF (4.1 mL) in a round-bottomedflask in an ice-cold condition under constant stirring. A solution of29.4 (3.00 g, 13.6 mmol) in DMF (15 mL) was added to the mixture andstirred for further 1 h, the reaction mixture was then heated to 70° C.for 4 h. After the reaction, the mixture was poured into 50 g of crushedice under constant manual stirring. After neutralization withsat.aq.K₂CO₃ solution, EtOAc (80 mL) was added. The organic phase wasseparated and the aqueous phase was extracted with EtOAc (80 mL×2). Thecombined organic layers were washed with water (80 mL) and brine (80mL), dried and concentrated in vacuo. The crude product was purified byrecrystallization from EtOH to afford 29.5 (2.20 g, 62.7% yield) asyellow solid. ¹H NMR (400 MHz, CDCl₃) δ 10.46 (s, 1H), 8.45 (s, 1H),7.63 (d, J=8.0 Hz, 2H), 7.30 (d, J=8.0 Hz, 2H), 4.52 (q, J=7.2 Hz, 2H),2.42 (s, 3H), 1.47 (t, J=7.2 Hz, 3H). LCMS (ESI+) m/z=259.0 (M+H).

Step 29.6: Synthesis of 2-p-tolyl-2H-pyrazolo[4,3-d]pyridazin-7(6H)-one(29.6)

29.5 (1.90 g, 7.36 mmol) and hydrazine hydrate (740 mg, 14.7 mmol) inEtOH (10 mL) was heated to reflux for 16 h. The mixture was then cooledto RT and the precipitate was filtered off and washed with EtOH, driedin vacuo to afford 29.6 (1.40 g, 84.3%) as white solid. ¹H NMR (400 MHz,DMSO-d6) δ 12.40 (br, 1H), 9.15 (s, 1H), 8.36 (s, 1H), 7.92 (d, J=8.0Hz, 2H), 7.42 (d, J=8.0 Hz, 2H), 2.40 (s, 3H). LCMS (ESI+) m/z=227.2(M+H).

Step 29.7: Synthesis of 7-chloro-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazine(29.7)

To a solution of 29.6 (1.40 g, 6.19 mmol) in MeCN (6 mL) was added POCl₃(2.80 g, 18.6 mmol) at RT. The reaction mixture was then stirred refluxfor 2 h. Upon completion, the mixture was concentrated in vacuo and theresidue was poured into ice-water. Then its pH was adjusted to 8 withsat. aq. NaHCO₃ solution, the aqueous layer was extracted with DCM (40mL×3). The combined organic layers were washed successively with water(40 mL), brine (40 mL) and then dried over Na₂SO₄, filtered and thefiltrate was concentrated to afford 29.7 (1.20 g, 79.5% yield) as yellowsolid. LCMS (ESI+) m/z=245.2 (M+H).

Step 29.8: Synthesis ofN-(3-(dimethylamino)propyl)-1-(2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(29)

To a solution of 29.7 (100 mg, 0.410 mmol) and 29.2 (114 mg, 0.533 mmol)in EtOH (8 mL) was added TEA (124 mg, 1.23 mmol) at RT. The reactionmixture was stirred reflux for 16 h. Upon completion, solvent wasremoved in vacuo, the residue was diluted with water (20 mL) andextracted with 10% MeOH/DCM (20 mL×3). The combined organic layers werewashed with brine (20 mL), dried over Na₂SO₄, filtered and concentratedin vacuo. The residue was purified on prep-HPLC and lyophilized toafford 29 (8 mg, 4.6% yield) as white solid. ¹H NMR (400 MHz, CD₃OD) δ8.96 (s, 1H), 8.87 (s, 1H), 7.89 (d, J=8.8 Hz, 2H), 7.42 (d, J=8.4 Hz,2H), 5.37 (d, J=13.2 Hz, 2H), 3.28-3.21 (m, 4H), 2.61 (tt, J=11.4 Hz,4.0 Hz, 1H), 2.45 (s, 3H), 2.41 (t, J=8.0 Hz, 2H), 2.29 (s, 6H),1.97-1.82 (m, 4H), 1.76-1.69 (m, 2H). LCMS (ESI+) m/z=422.4 (M+H).

Example 8 Synthesis of Compound No. 53N-(3-(dimethylamino)propyl)-1-(1-methyl-2-(p-tolyl)-1H-benzo[d]imidazol-4-yl)piperidine-4-carboxamide

Step 53.1: Synthesis ofN-(2-bromo-6-(methylamino)phenyl)-4-methylbenzamide (53.1)

To a solution of 3-bromo-N¹-methylbenzene-1,2-diamine (2.0 g, 10 mmol)and TEA (2.75 ml, 20 mmol) in DCM (30 mL) was added 4-methylbenzoylchloride (1.3 g, 8.7 mmol) dropwise under ice-water bath. The reactionmixture was then stirred at RT for 16 h. Then the reaction mixture wasconcentrated to provide 53.1 (2.7 g, 97.5% yield) as brown oil, whichwas used directly in next step without further purification.

Step 53.2: Synthesis of 4-bromo-1-methyl-2-p-tolyl-1H-benzo[d]imidazole(53.2)

To a solution of 53.1 (2.7 g, 8.46 mmol) in HOAc (24 mL) was addedconc.HCl (0.6 ml) at RT. The reaction mixture was then stirred at RT for16 h. Upon completion, solvent was removed under reduced pressure. Theresidue was dissolved in DCM (150 mL) and washed with sat. aq. NaHCO₃solution (100 mL). The organic layer was dried over Na₂SO₄ andconcentrated in vacuo. The crude product was recrystallized with MTBE toprovide 53.2 (2.1 g, 82.5% yield) as brown solid. LCMS (ESI+) m/z=301(M+H).

Step 53.3: Synthesis of ethyl1-(1-methyl-2-p-tolyl-1H-benzo[d]imidazol-4-yl) piperidine-4-carboxylate(53.3)

To a solution of 53.2 (1.4 g, 4.65 mmol), ethyl piperidine-4-carboxylate(876 mg, 5.58 mmol), X-Phos (887 mg, 1.86 mmol) and NaOt-Bu (625 mg,6.52 mmol) in PhMe (55 ml) was added Pd₂dba₃ (426 mg, 0.465 mmol) underAr atmosphere. The resulting mixture was heated to 85° C. for 40 h. Themixture was then concentrated in vacuo. The residue was dissolved in DCM(100 mL) and washed with water (80 mL) and brine (60 mL). The organiclayer was dried over Na₂SO₄ and concentrated in vacuo. The residue waspurified by column chromatography on silica gel to give 53.3 (400 mg,23% yield) as yellow solid. LCMS (ESI+) m/z=378 (M+H).

Step 53.4: Synthesis of1-(1-methyl-2-p-tolyl-1H-benzo[d]imidazol-4-yl)piperidine-4-carboxylicacid (53.4)

To a solution of 53.3 (360 mg, 0.95 mmol) in MeOH (12 mL) was added INaq. LiOH solution (3 mL) dropwise. The reaction mixture was then stirredat RT for 2 h. MeOH was removed in vacuo and the aqueous layer wasadjusted to pH=6 with IN aq. HCl solution, the formed solid wascollected by filtration to give 53.4 (135 mg, 40.5% yield) as a whitesolid. LCMS (ESI+) m/z=350 (M+H).

Step 53.5: Synthesis ofN-(3-(dimethylamino)propyl)-1-(1-methyl-2-(p-tolyl)-1H-benzo[d]imidazol-4-yl)piperidine-4-carboxamide(53)

To a solution of 53.4 (105 mg, 0.30 mmol),N¹,N¹-dimethylpropane-1,3-diamine (46 mg, 0.45 mmol), HOBt (81 mg, 0.60mmol) and TEA (0.13 ml, 0.90 mmol) in DCM (8 mL) was added EDCI (115 mg,0.60 mmol) portionwise under ice-water bath. The reaction mixture wasthen stirred at RT for 16 h. Upon completion, the reaction mass wasdiluted with DCM (30 mL) and washed with water (25 mL) and brine (25mL). The organic layer was dried over Na₂SO₄ and concentrated in vacuo.The crude product was purified by prep-HPLC and lyophilized to afford 53(66 mg, 50.8% yield) as white solid. ¹H NMR (400 MHz, DMSO-d6) δ 7.81(t, J=5.5 Hz, 1H), 7.70 (d, J=8.1 Hz, 2H), 7.38 (d, J=7.9 Hz, 2H), 7.12(t, J=7.9 Hz, 1H), 7.05 (d, J=7.5 Hz, 1H), 6.59 (d, J=7.4 Hz, 1H), 4.37(d, J=12.0 Hz, 2H), 3.79 (s, 3H), 3.05 (dd, J=12.6, 6.8 Hz, 2H),2.80-2.67 (m, 2H), 2.41 (s, 3H), 2.32-2.24 (m, 1H), 2.17 (dd, J=15.1,7.8 Hz, 2H), 2.10 (s, 6H), 1.84-1.69 (m, 4H), 1.56-1.47 (m, 2H). LCMS(ESI+) m/z=434 (M+H).

Example 9 Synthesis of Compound No. 55N-(3-(dimethylamino)propyl)-1-(2-(p-tolyl)-2H-pyrazolo[4,3-c]pyridin-7-yl)piperidine-4-carboxamide

Step 55.1: Synthesis of 5-bromo-4-chloronicotinaldehyde (55.1)

To a solution of diisopropylamine (7.6 g, 74.8 mmol) in THF (66 mL) at−30° C. was added 2.5 M n-BuLi in THF (30 mL). The reaction mixture wasstirred for 30 min then cooled to −78° C. A suspension of3-bromo-4-chloropyridine (12.0 g, 62.4 mmol) in THF (24 mL) was addeddropwise over 20 min, then the mixture was stirred at −78° C. for 3.5 h.DMF (5.46 g, 74.8 mmol) was added and the reaction was warmed to RT for30 min. The reaction mixture was quenched with NH₄Cl (360 mL) andextracted with EtOAc (120 mL×3). The combined organic layers were washedwith brine (240 mL), dried over Na₂SO₄ and concentrated in vacuo. Theresidue was purified by column chromatography on silica gel (PE/EA=15/1)to afford 55.1 (8.0 g, 58% yield) as pale yellow solid. H NMR (400 MHz,CDCl₃) δ 10.48 (s, 1H), 8.94 (d, J=3.4 Hz, 2H).

Step 55.2: Synthesis of 4-azido-5-bromonicotinaldehyde (55.2)

A mixture of 55.1 (3.0 g, 13.6 mmol) and NaN₃ (929 mg, 14.3 mmol) in DMF(9 mL) was stirred at RT overnight. The completion of the reaction wasmonitored by TLC. The mixture was then quenched with brine (120 mL) andextracted with EtOAc (40 mL×3). The combined organic layers were washedwith brine (60 mL), dried over Na₂SO₄ and concentrated in vacuo to give55.2 (4.1 g, 100% yield) as pale yellow solid. ¹H NMR (400 MHz, CDCl₃) δ10.31 (s, 1H), 8.86 (s, 1H), 8.80 (s, 1H).

Step 55.3: Synthesis ofN-((4-azido-5-bromopyridin-3-yl)methylene)-4-methylaniline (55.3)

To a cooled (0° C.) solution of 55.3 (4.1 g, 18.1 mmol), p-toluidine(1.9 g, 18.1 mmol) and TEA (5.5 g, 54.3 mmol) in DCM (80 mL) was added1.0 M TiCl₄ (10.9 mL) dropwise over 20 min. The reaction mixture wasstirred for 20 min, warm to RT and then stirred for additional 2 h. Theresultant mixture was concentrated to dryness to afford 55.3 (5.7 g) asbrown solid, which was used without further purification.

Step 55.4: Synthesis of 7-bromo-2-p-tolyl-2H-pyrazolo[4,3-c]pyridine(55.4)

A solution of 55.3 (5.7 g) in PhMe was heated to reflux overnight. Uponcompletion, solvent was removed under vacuo. The residue was purified bycolumn chromatography on silica gel to afford 55.4 (2.6 g, 50% yield) aspale yellow solid.

Step 55.5: Synthesis of ethyl1-(2-p-tolyl-2H-pyrazolo[4,3-c]pyridin-7-yl)piperidine-4-carboxylate(55.5)

To a solution of 55.4 (1.4 g, 5.00 mmol), ethyl piperidine-4-carboxylate(942 mg, 6.00 mmol), X-phos (954 mg, 2.00 mmol) and t-BuONa (672 mg,7.00 mmol) in PhMe (60 mL) was added Pd₂dba₃ (458 mg, 0.5 mmol) under Aratmosphere. The resulting mixture was heated to 85° C. for 20 h. Themixture was then concentrated in vacuo. The residue was dissolved in DCM(100 mL) and washed with water (80 mL) and brine (60 mL). The organiclayer was dried over Na₂SO₄ and concentrated in vacuo. The residue waspurified by column chromatography on silica gel (DCM/MeOH=20/1) toafford 55.5 (640 mg, 35% yield) as yellow solid. LCMS (ESI+) m/z=365(M+H).

Step 55.6: Synthesis of1-(2-p-tolyl-2H-pyrazolo[4,3-c]pyridin-7-yl)piperidine-4-carboxylic Acid(55.6)

To a solution of 55.5 (620 mg, 1.70 mmol) in MeOH (5 mL) was added INaq. LiOH solution (5.1 mL) dropwise. The reaction mixture was thenstirred at RT for 2 h. MeOH was removed in vacuo and the aqueous layerwas adjusted to pH=6 with IN aq. HCl solution, the formed solid wascollected by filtration to get 55.6 (500 mg, 87% yield) as a yellowsolid. LCMS (ESI+) m/z=337 (M+H).

Step 55.7: Synthesis ofN-(3-(dimethylamino)propyl)-1-(2-(p-tolyl)-2H-pyrazolo[4,3-c]pyridin-7-yl)piperidine-4-carboxamide(55)

To a solution of 55.6 (100 mg, 0.30 mmol) andN¹,N¹-dimethylpropane-1,3-diamine (46 mg, 0.45 mmol) in DMF (3 mL) wasadded DIPEA (116 mg, 0.90 mmol), followed by the addition of HATU (228mg, 0.60 mmol) portionwise. The reaction mixture was stirred at 30° C.overnight. 10% aq. NaCl (35 mL) solution was added and the mixture wasextracted with EtOAc (20 mL×3). The combined organic layers were washedwith 10% aq. NaCl (20 mL×2) and brine (20 mL), dried over Na₂SO₄ andconcentrated in vacuo. The residue was was purified by prep-HPLC andlyophilized to afford 55 (12 mg, 9.5% yield) as yellow solid. ¹H NMR(400 MHz, MeOD-d4) δ 9.00 (s, 1H), 8.70 (s, 1H), 7.91 (d, J=8.5 Hz, 2H),7.57 (s, 1H), 7.41 (d, J=8.5 Hz, 2H), 4.43 (d, J=12.3 Hz, 2H), 3.23 (t,J=6.9 Hz, 2H), 2.92 (td, J=12.1, 2.8 Hz, 2H), 2.49-2.38 (m, 6H), 2.28(s, 6H), 2.06-1.90 (m, 4H), 1.76-1.68 (m, 2H). LCMS (ESI+) m/z=421.4(M+H).

Example 10 Synthesis of Compound No. 764-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)piperazine-1-carboxamide

Step 76.1: Synthesis ofN-(3-(dimethylamino)propyl)-1-(2-p-tolyl-2H-pyrazolo[4,3-c]pyridine-7-yl)piperidine-4-carboxamide(76.1)

To a solution of 1.4 (300 mg, 1.10 mmol) and tert-butylpiperazine-1-carboxylate (246 mg, 1.32 mmol) in EtOH (20 mL) was addedTEA (334 mg, 3.31 mmol). The resulting mixture was heated to refluxovernight. Upon completion, solvent was removed in vacuo, the residuewas diluted with water (30 mL) and extracted with 10% MeOH/DCM (30mL×3). The combined organic layers were washed with brine (20 mL), driedover Na₂SO₄, filtered and concentrated in vacuo. The residue waspurified by column chromatography on silica gel (DCM/MeOH=20/1) toafford 76.1 (440 mg, 95% yield) as yellow solid. LCMS (ESI+) m/z=423(M+H).

Step 76.2: Synthesis of3,4-dimethyl-7-(piperazin-1-yl)-2-p-tolyl-2H-pyrazolo[3,4-d]pyridazine(76.2)

To a solution of 76.1 (440 mg, 1.04 mmol) in MeOH (20 mL) was added 4 MHCl in 1,4-dioxane (20 mL) dropwise. The resulting mixture was stirredat RT for 1 h. Solvent was then removed in vacuo, the residue wasdissolved with water (10 mL) and then adjusted to pH=8 with satu. aq.Na₂CO₃ solution. The aqueous phase was extracted with 10% MeOH/DCM (30mL×3). The combined organic layers were washed with brine (20 mL), driedover Na₂SO₄ and concentrated in vacuo to afford 76.2 (260 mg, 77.6%yield) as yellow solid. LCMS (ESI+) m/z=323 (M+H).

Step 76.3: Synthesis of(4-(3,4-dimethyl-2-p-tolyl-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperazin-1-yl)(1H-imidazol-1-yl)methanone(76.3)

To a solution of CDI (99 mg, 0.615 mmol) in DCM (10 mL) was added TEA(169 mg, 1.68 mmol), followed by addition of 76.2 (180 mg, 0.559 mmol)portionwise under ice-water bath. The resulting mixture was stirred atthe same temperature for 2 h. The mixture was then diluted with DCM (20mL) and washed with water (15 mL×2). The organic layer was dried overNa₂SO₄ and concentrated in vacuo to afford 76.3 (223 mg, 95% yield) aspale yellow solid. LCMS (ESI+) m/z=417 (M+H).

Step 76.4: Synthesis of4-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)piperazine-1-carboxamide(76)

To a solution of 76.3 (200 mg, 0.481 mmol) in MeCN (15 mL) was addedN¹,N¹-dimethylpropane-1,3-diamine (980 mg, 9.62 mmol) and K₂CO₃ (265 mg,1.92 mmol). The reaction mixture was heated to reflux for 48 h. Themixture was then diluted with DCM (45 mL) and washed with water (20 mL)and brine (20 mL). The organic layer was dried over Na₂SO₄ andconcentrated in vacuo. The residue was recrystallized in MeCN to afford76 (45 mg, 21% yield) as white solid. ¹H NMR (400 MHz, DMSO-d6) δ 7.52(d, J=8.3 Hz, 2H), 7.44 (d, J=8.2 Hz, 2H), 6.62 (t, J=5.3 Hz, 1H),3.94-3.92 (m, 4H), 3.43-3.41 (m, 4H), 3.05 (dd, J=12.7, 6.6 Hz, 2H),2.68 (d, J=5.7 Hz, 6H), 2.43 (s, 3H), 2.19 (t, J=7.1 Hz, 2H), 2.10 (s,6H), 1.57-1.50 (m, 2H). LCMS (ESI+) m/z=451.3 (M+H).

Example 11 Synthesis of Compound No. 34N-(3-(dimethylamino)propyl)-1-(4-methyl-3-phenyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide

Step 34.1: Synthesis of ethyl 2-chloro-2-(2-p-tolylhydrazono)acetate(34.1)

A solution of p-toluidine (10.0 g, 93.5 mmol) in dilute HCl (1:1, 66 mL)was cooled to 0° C., and a cold solution of NaNO₂ (7.10 g, 103 mmol) inH₂O (90 mL) was added dropwise over 20 min while maintaining internalsolution temperature below 5° C. After addition, the reaction mixturewas stirred for further 30 min keeping the internal temperature below 0°C. The resulting ice-cold solution was then added dropwise to apre-cooled (0° C.) solution of ethyl 2-chloro-3-oxobutanoate (15.3 g,93.5 mmol) and NaOAc (11.5 g, 140 mmol) in H₂O/EtOH (1:7, 370 mL). Uponcompletion of addition, the reaction mixture was stirred for 4 h at thesame temperature and then quenched by addition of cold water. Theresultant precipitate was filtered and dried in vacuo to give 34.1 (18.0g, 80.0% yield) as pale yellow solid. ¹H NMR (400 MHz, CDCl₃) δ 8.31 (s,1H), 7.15-7.10 (m, 4H), 4.38 (q, J=7.1 Hz, 2H), 2.31 (s, 3H), 1.40 (t,J=7.1 Hz, 3H). LCMS (ESI+) m/z=241 (M+H).

Step 34.2: Synthesis of ethyl4-acetyl-5-phenyl-1-p-tolyl-1H-pyrazole-3-carboxylate (34.2) and ethyl4-benzoyl-5-methyl-1-p-tolyl-1H-pyrazole-3-carboxylate (35.1)

A solution of 1-phenylbutane-1,3-dione (6.75 g, 41.7 mmol) in anhydrousEtOH (40 mL) was added dropwise to a solution of NaOEt (3.12 g, 45.8mmol) in anhydrous EtOH (25 mL) under ice-water bath. The resultingmixture was heated to 50° C. for 15 min. 34.1 (10.0 g, 41.7 mmol) wasadded portionwise after the mixture was cooled to RT. The reactionmixture was then stirred at RT for 16 h. Upon completion, the solventwas removed in vacuo, the residue was diluted with DCM (200 mL) andwashed with water (100 mL) and brine (100 mL). The organic layer wasconcentrated in vacuo, the residue was purified by column chromatographyon silica gel (PE/EA=5/1) to afford a mixture of 34.2 and 35.1 (7.20 g,49.6% total yield) as yellow solid. LCMS (ESI+) m/z=349.3 (M+H).

Step 34.3: Synthesis of4-methyl-3-phenyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazin-7(6H)-one (34.3)and 3-methyl-4-phenyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazin-7(6H)-one(35.2)

A mixture of 34.2 and 35.1 (2.00 g, 5.75 mmol) was dissolved in EtOH (32mL) and then hydrazine hydrate (2.88 g, 57.5 mmol) was added to thesolution. The reaction mixture was heated to reflux for 16 h. Themixture was then cooled to RT and the precipitate was filtered off,washed with EtOH and dried in vacuo. The residue was purified byprep-HPLC and lyophilized to afford 34.3 (410 mg, 22.6% yield) as whitesolid and 35.2 (255 mg, 14.0% yield) as white solid. 34.3: ¹H NMR (400MHz, CD₃OD) δ 7.52-7.40 (m, 5H), 7.26-7.24 (m, 2H), 7.18 (d, J=8.2 Hz,2H), 2.34 (s, 3H), 2.09 (s, 3H). LCMS (ESI+) m/z=317.2 (M+H); 35.2: ¹HNMR (400 MHz, CD₃OD) δ 7.63-7.60 (m, 2H), 7.55-7.53 (m, 3H), 7.49-7.47(m, 2H), 7.42 (d, J=8.3 Hz, 2H), 2.46 (s, 3H), 2.18 (s, 3H). LCMS (ESI+)m/z=317.2 (M+H).

Step 34.4: Synthesis of7-chloro-4-methyl-3-phenyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazine (34.4)

A round bottom flask was charged 34.3 (316 mg, 1.00 mmol) and POCl₃ (5mL), the reaction mixture was heated to reflux for 5 h. Upon completion,POCl₃ was removed in vacuo, the residue was diluted with water (15 mL)and adjusted PH to 8 with sat. aq. NaHCO₃ solution. The aqueous layerwas extracted with 10% MeOH/DCM (20 mL×2). The combined organic layerswere washed with brine (20 mL), dried over Na₂SO₄, filtered andconcentrated in vacuo. The residue was purified by column chromatographyon silica gel (PE/EA=1/1) to afford 34.4 (300 mg, 89.6% yield) as yellowsolid. ¹H NMR (400 MHz, CD₃OD) δ 7.56-7.44 (m, 5H), 7.34-7.32 (m, 2H),7.24 (d, J=8.1 Hz, 2H), 2.46 (s, 3H), 2.37 (s, 3H). LCMS (ESI+)m/z=335.2 (M+H).

Step 34.5: Synthesis ofN-(3-(dimethylamino)propyl)-1-(4-methyl-3-phenyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(34)

To a solution of 34.4 (260 mg, 0.778 mmol) and 29.2 (249 mg, 1.17 mmol)in EtOH (10 mL) was added TEA (354 mg, 3.50 mmol) at RT. The reactionmixture was stirred reflux for 16 h. Upon completion, solvent wasremoved in vacuo, the residue was diluted with water (40 mL) andextracted with 10% MeOH/DCM (30 mL×3). The combined organic layers werewashed with brine (40 mL), dried over Na₂SO₄, filtered and concentratedin vacuo. The residue was purified on prep-HPLC and lyophilized toafford 34 (89 mg, 22% yield) as yellow solid. ¹H NMR (400 MHz, MeOD-d4)δ 7.51-7.43 (m, 3H), 7.41-7.39 (m, J=6.9, 2H), 7.26 (d, J=7.2 Hz, 2H),7.19 (d, J=7.5 Hz, 2H), 5.27 (d, J=13.3 Hz, 2H), 3.23-3.13 (m, 4H),2.59-2.51 (m, 1H), 2.39-2.35 (m, 5H), 2.25 (t, J=3.8 Hz, 9H), 1.90-1.80(m, 4H), 1.72-1.66 (m, 2H). LCMS (ESI+) m/z=512.4 (M+H).

Compound Nos. 23 and 63 were prepared using the appropriate startingmaterials and reagents according to the same procedures as in Example11.

Example 12 Synthesis of Compound Nos. 23 and 63

LCMS Compound ¹H NMR (400 MHz) m/z No. Structure (Solvent) δ ppm (M + H)23

(DMSO-d6) δ 8.90 (d, J = 2.2 Hz, 1H), 8.81 (dd, J = 4.8, 1.4 Hz, 1H),8.17 (ddd, J = 8.2, 2.5, 1.5 Hz, 1H), 7.81 (t, J = 5.6 Hz, 1H),7.73-7.69 (m, 1H), 5.01 (d, J = 13.0 Hz, 2H), 3.06-3.00 (m, 4H), 2.70(d, J = 10.0 Hz, 6H), 2.46-2.38 (m, 1H), 2.16 (t, J = 7.2 Hz, 2H), 2.09(s, 6H), 1.73 (dd, J = 12.4, 2.2 Hz, 2H), 1.67-1.57 (m, 2H), 1.53- 1.46(m, 2H). 437 63

(DMSO-d6) δ 7.73 (t, J = 5.5 Hz, 1H), 7.57 (d, J = 8.3 Hz, 2H), 7.44 (d,J = 8.1 Hz, 2H), 5.02 (d, J = 13.1 Hz, 2H), 3.15- 3.08 (m, 4H), 2.66 (d,J = 1.9 Hz, 3H), 2.48-2.44 (m, 4H), 2.24 (t, J = 6.8 Hz, 2H), 2.12 (s,6H), 1.76-1.73 (m, 2H), 1.67- 1.57 (m, 2H). 490

Example 13 Synthesis of Compound No. 35N-(3-(dimethylamino)propyl)-1-(3-methyl-4-phenyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide

Step 35.1: Synthesis of7-chloro-3-methyl-4-phenyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazine (35.3)

A round bottom flask was charged 35.2 (160 mg, 0.506 mmol) and POCl₃ (3mL), the reaction mixture was heated to reflux for 5 h. Upon completion,POCl₃ was removed in vacuo, the residue was diluted with water (10 mL)and adjusted PH to 8 with sat. aq. NaHCO₃ solution. The aqueous layerwas extracted with 10% MeOH/DCM (20 mL×2). The combined organic layerswere washed with brine (20 mL), dried over Na₂SO₄, filtered andconcentrated in vacuo. The residue was purified by column chromatographyon silica gel (PE/EA=1/1) to afford 35.3. (150 mg, 88% yield) as yellowsolid. 1H NMR (400 MHz, DMSO-d6) δ 7.79-7.75 (m, 2H), 7.62-7.59 (m, 5H),7.47 (d, J=8.1 Hz, 2H), 2.44 (s, 3H), 2.31 (s, 3H). LCMS (ESI+) m/z=335(M+H).

Step 35.2: Synthesis ofN-(3-(dimethylamino)propyl)-1-(3-methyl-4-phenyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(35)

To a solution of 35.3 (150 mg, 0.449 mmol) and 29.2 (124 mg, 0.584 mmol)in EtOH (10 mL) was added TEA (136 mg, 1.35 mmol) at RT. The reactionmixture was stirred reflux for 16 h. Upon completion, solvent wasremoved in vacuo, the residue was diluted with water (20 mL) andextracted with 10% MeOH/DCM (20 mL×3). The combined organic layers werewashed with brine (30 mL), dried over Na₂SO₄, filtered and concentratedin vacuo. The residue was purified on prep-HPLC and lyophilized toafford 35 (73 mg, 32% yield) as pale yellow solid. ¹H NMR (400 MHz,MeOD) δ 7.63-7.61 (m, 2H), 7.56-7.51 (m, 3H), 7.47 (d, J=8.4 Hz, 2H),7.42 (d, J=8.2 Hz, 2H), 5.33 (d, J=13.2 Hz, 2H), 3.22-3.15 (m, 4H),2.62-2.53 (m, 1H), 2.46 (s, 3H), 2.38-2.34 (m, 2H), 2.23 (d, J=12.1 Hz,9H), 1.90-1.80 (m, 4H), 1.73-1.66 (m, 2H). LCMS (ESI+) m/z=512.3 (M+H).

Example 14 Synthesis of Compound Nos. 36 and 481-(4-chloro-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)piperidine-4-carboxamideAnd1-(7-chloro-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-4-yl)-N-(3-(dimethylamino)propyl)piperidine-4-carboxamide

Step 36.1: Synthesis of 4-ethyl 1-methyl 2-acetyl-3-aminofumarate (36.1)

To a solution of methyl 3-oxobutanoate (9.8 g, 84.4 mmol) in DCM (20 mL)were added ethyl carbonocyanidate (12.5 g, 126 mmol) and Zn(acac)₂ (445mg, 1.69 mmol). The mixture was stirred at RT under Ar atmosphereovernight. Solvent was then removed under reduced pressure. The residuewas treated with EtOAc (30 mL) and the suspension was filtered overcelite. The clear filtrate was evaporated in vacuo to give 36.1 (15.8 g,87% yield) as white solid. LCMS (ESI+) m/z=216 (M+H).

Step 36.2: Synthesis of 3-ethyl 4-methyl5-methyl-1-p-tolyl-1H-pyrazole-3,4-dicarboxylate (36.2)

To a stirred and cooled (0° C.) solution of 36.1 (19.0 g, 88.4 mmol) inDCM (150 mL) was added a cooled solution of p-tolylhydrazine (16.2 g,132 mmol) in DCM (180 mL) dropwise over 30 min. The resulting mixturewas stirred at the same temperature overnight. The mixture was thendiluted with DCM (800 mL) and washed with 0.5 N aq. HCl solution (400mL), water (400 mL) and brine (400 mL). The organic layer was dried overNa₂SO₄ and concentrated in vacuo. The residue was recrystallized in EtOHand filtered, the precipitate was collected to give 36.2 (21.0 g, 79%yield) as pale yellow solid. LCMS (ESI+) m/z=303 (M+H).

Step 36.3: Synthesis of3-methyl-2-p-tolyl-5,6-dihydro-2H-pyrazolo[4,3-d]pyridazine-4,7-dione(36.3)

To a solution of 36.2 (11.1 g, 36.8 mmol) in EtOH (45 mL) was addedhydrazine hydrate (18.4 g, 368 mmol) at RT. The reaction mixture wasthen heated to reflux overnight. After that the mixture was cooled to RTand the precipitate was collected by filtration to get 36.3 (7.77 g,82.7% yield) as a white solid. LCMS (ESI+) m/z=257 (M+H).

Step 36.4: Synthesis of4,7-dichloro-3-methyl-2-p-tolyl-2H-pyrazolo[4,3-d]pyridazine (36.4)

To a solution of 36.3 (2.6 g, 10.2 mmol) in MeCN (3 mL) was added POCl₃(7.8 g, 50.8 mmol) at RT. The reaction mixture was then stirred refluxfor 2 h. Upon completion, the mixture was concentrated in vacuo and theresidue was poured into ice-water. Then its pH was adjusted to 8 withsat. aq. NaHCO₃ solution, the aqueous layer was extracted with DCM (50mL×3). The combined organic layers were washed successively with water(50 mL), brine (50 mL) and then dried over Na₂SO₄, filtered and thefiltrate was concentrated in vacuo. The residue was purified by columnchromatography on silica gel (PE/EA=1/1) to afford 36.4 (2.3 g, 76.9%yield) as yellow solid. LCMS (ESI+) m/z=293 (M+H).

Step 36.5: Synthesis of1-(4-chloro-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)piperidine-4-carboxamide(36) and1-(7-chloro-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-4-yl)-N-(3-(dimethylamino)propyl)piperidine-4-carboxamide(48)

To a solution of 36.4 (1.0 g, 3.42 mmol) and 29.2 (650 mg, 3.25 mmol) inEtOH (10 mL) was added TEA (1.0 g, 10.2 mmol) at RT. The reactionmixture was stirred reflux for 2 h. Upon completion, solvent was removedin vacuo, the residue was diluted with water (40 mL) and extracted with10% MeOH/DCM (30 mL×3). The combined organic layers were washed withbrine (40 mL), dried over Na₂SO₄, filtered and concentrated in vacuo.The residue was purified on prep-HPLC and lyophilized to afford 36 (400mg, 24.9% yield) as white solid and 48 (120 mg, 7.5%) as white solid.36: ¹H NMR (400 MHz, DMSO-d6) δ 7.81 (t, J=5.6 Hz, 1H), 7.56 (d, J=8.3Hz, 2H), 7.45 (d, J=8.1 Hz, 2H), 5.06 (d, J=13.1 Hz, 2H), 3.14-3.08 (m,2H), 3.03 (dd, J=12.6, 6.8 Hz, 2H), 2.69 (s, 3H), 2.47-2.43 (m, 4H),2.16 (t, J=7.2 Hz, 2H), 2.08 (s, 6H), 1.76 (dd, J=12.6, 2.3 Hz, 2H),1.61 (qd, J=12.6, 3.8 Hz, 2H), 1.53-1.46 (m, 2H). LCMS (ESI+) m/z=470.4(M+H); 48: ¹H NMR (400 MHz, DMSO-d6) δ 7.88 (t, J=5.5 Hz, 1H), 7.61 (d,J=8.3 Hz, 2H), 7.46 (d, J=8.2 Hz, 2H), 3.87 (d, J=12.9 Hz, 2H), 3.07(dd, J=12.6, 6.8 Hz, 2H), 3.02-2.95 (m, 2H), 2.64 (s, 3H), 2.44 (s, 3H),2.41-2.35 (m, 1H), 2.19 (t, J=7.1 Hz, 2H), 2.10 (s, 6H), 1.86-1.73 (m,4H), 1.56-1.49 (m, 2H). LCMS (ESI+) m/z=470.3 (M+H).

Example 15 Synthesis of Compound No. 41N-(3-(dimethylamino)propyl)-1-(4-iodo-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide

Step 41.1: Synthesis ofN-(3-(dimethylamino)propyl)-1-(4-iodo-3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(41)

To a solution of 36 (100 mg, 0.213 mmol) and NaI (640 mg, 4.26 mmol) inbutanone (5 mL) was added TFA (122 mg, 1.07 mmol) dropwise underice-water bath. The resulting mixture was heated to reflux overnight.After that the mixture was cooled to RT and added to sat. aq. NaHCO₃solution slowly under ice-water bath. The mixture was then extractedwith 10% MeOH/DCM (40 mL) and the organic layer was washed with aq.NaHSO₃ (30 mL), dried over Na₂SO₄ and concentrated in vacuo. The residuewas purified on prep-HPLC and lyophilized to afford 41 (4 mg, 3.3%yield) as yellow solid. ¹H NMR (400 MHz, MeOD-d4) δ 7.47-7.42 (m, 4H),5.23 (d, J=13.3 Hz, 2H), 3.21-3.10 (m, 4H), 2.74 (s, 3H), 2.57-2.50 (m,1H), 2.48 (s, 3H), 2.36-2.32 (m, 2H), 2.24 (s, 6H), 1.88-1.74 (m, 4H),1.72-1.64 (m, 2H). LCMS (ESI+) m/z=562.2 (M+H).

Example 16 Synthesis of Compound No. 42N-(3-(dimethylamino)propyl)-1-(3-methyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide

Step 42.1: Synthesis ofN-(3-(dimethylamino)propyl)-1-(3-ethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide(42)

To a solution of 36 (70 mg, 0.149 mmol) and NaI (448 mg, 2.99 mmol) inbutanone (3.5 mL) was added TFA (0.35 mL) dropwise under ice-water bath.The resulting mixture was stirred at 90° C. in a sealed tube overnight.After that the mixture was cooled to RT and added to sat. aq. NaHCO₃solution slowly under ice-water bath. The mixture was then extractedwith 10% MeOH/DCM (30 mL) and the organic layer was washed with aq.NaHSO₃ (20 mL), dried over Na₂SO₄ and concentrated in vacuo. The residuewas purified on prep-HPLC and lyophilized to afford 42 (13 mg, 20.4%yield) as yellow solid. ¹H NMR (400 MHz, MeOD-d4) δ 8.83 (s, 1H), 7.50(d, J=8.3 Hz, 2H), 7.43 (d, J=8.3 Hz, 2H), 5.28 (d, J=13.4 Hz, 2H),3.21-3.12 (m, 4H), 2.64 (s, 3H), 2.59-2.51 (m, 1H), 2.47 (s, 3H),2.38-2.34 (m, 2H), 2.25 (s, 6H), 1.90-1.76 (m, 4H), 1.72-1.65 (m, 2H).LCMS (ESI+) m/z=436.4 (M+H).

Compound Nos. 16, 20, 24, 25, 27, 38, 43-45, 57, 58, 65-75, 15x, 17x,and 45x were prepared using the appropriate starting materials andreagents according to the same procedures as in Example 1.

Example 17 Synthesis of Compound Nos. 16, 20, 24, 25, 27, 38, 43-45, 57,58, 65-75, 15x, 17x, and 45x

LCMS Compound ¹H NMR (400 MHz) m/z No. R^(E) R¹ (Solvent) δ ppm (M + H)16 

(MeOD-d4) 7.48-7.43 (m, 4H), 5.01-4.94 (m, 2H), 3.39-3.34 (m, 2H),3.29-3.21 (m, 2H), 2.93-2.83 (m, 1H), 2.75-2.71 (m, 8H), 2.60 (tt, J =10.3, 3.8 Hz, 1H), 2.48 (s, 3H), 1.99-1.77 (m, 3H), 1.70-1.59 (m, 1H),1.08 (d, J = 6.3 Hz, 6H). 450 20 

(DMSO-d6) 7.74 (t, J = 5.5 Hz, 1H), 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J= 8.2 Hz, 2H), 4.38 (dd, J = 9.3, 4.5 Hz, 2H), 3.50 (t, J = 10.3 Hz,2H), 3.10 (dd, J = 12.5, 6.7 Hz, 2H), 2.65 (d, J = 0.9 Hz, 6H), 2.43 (s,3H), 2.18 (t, J = 7.1 Hz, 2H), 2.09-2.05 (m, 8H), 1.53 (p, J = 7.0 Hz,2H), 1.45-1.38 (m, 2H), 1.10 (s, 3H). 464 24 

(MeOD-d4) 7.82 (dd, J = 3.2, 1.4 Hz, 1H), 7.69 (dd, J = 5.2, 3.2 Hz,1H), 7.41 (dd, J = 5.2, 1.4 Hz, 1H), 5.18 (d, J = 13.3 Hz, 2H), 3.20 (t,J = 6.9 Hz, 2H), 3.14-3.07 (m, 2H), 2.79 (s, 3H), 2.74 (s, 3H), 2.56-2.48 (m, 1H), 2.36 (dd, J = 8.6, 6.9 Hz, 2H), 2.25 (s, 6H), 1.88-1.76(m, 4H), 1.72-1.65(m, 2H) 442 25 

(DMSO-d6) 7.89 (t, J = 5.4 Hz, 1H), 5.06 (t, J = 11.3 Hz, 1H), 4.05 (dd,J = 11.3, 3.5 Hz, 2H), 3.44 (t, J = 12.1 Hz, 4H), 3.08 (dd, J = 12.6,6.7 Hz, 2H), 2.90 (br, 2H), 2.76 (s, 3H), 2.63 (s, 3H), 2.36 (br, 1H),2.20 (t, J = 7.2 Hz, 2H), 2.15- 2.08 (m, 8H), 1.87-1.77 (m, 6H),1.57-1.50 (m, 2H). 444 27 

(MeOD-d4) 5.45-5.35 (m, 1H), 3.59 (d, J = 12.7 Hz, 2H), 3.24 (t, J = 7.0Hz, 2H), 2.99 (br, 2H), 2.83 (s, 3H), 2.70 (s, 3H), 2.49-2.37 (m, 3H),2.27 (s, 6H), 2.04-1.96 (m, 4H), 1.76-1.69 (m, 2H), 1.53 (d, J = 6.6 Hz,6H). 402 38 

(DMSO-d6) 7.77 (t, J = 5.5 Hz, 1H), 7.51 (d, J = 8.3 Hz, 2H), 7.44 (d, J= 8.3 Hz, 2H), 5.01 (d, J = 12.8 Hz, 2H), 3.05-2.98 (m, 4H), 2.66 (d, J= 3.7 Hz, 6H), 2.43-2.38 (m, 4H), 2.13 (t, J = 14.4 Hz, 1H), 2.07 (s,6H), 1.73-1.56 (m, 4H), 1.33 (dd, J = 15.0, 9.1 Hz, 4H), 1.27-1.22 (m,4H). 492 43 

(DMSO-d6) 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J = 8.2 Hz, 2H), 5.01 (t, J= 9.8 Hz, 2H), 4.40 (d, J = 12.6 Hz, 1H), 4.05 (d, J = 13.0 Hz, 1H),3.12-2.93 (m, 4H), 2.72-2.66 (m, 7H), 2.45 (t, J = 7.8 Hz, 8H),1.74-1.55 (m, 6H), 1.36-1.27 (m, 6H), 1.20-1.10 (m, 1H), 0.94 (t, J =7.1 Hz, 6H). 504 44 

(DMSO-d6) 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J = 8.2 Hz, 2H), 5.04 (d, J= 12.9 Hz, 2H), 3.82-3.69 (m, 1H), 3.58-3.44 (m, 1H), 3.24-2.90 (m, 1H),2.83-2.71 (m, 1H), 2.66 (d, J = 3.6 Hz, 6H), 2.58 (dd, J = 15.1, 7.8 Hz,1H), 2.43 (s, 3H), 2.17 (s, 3H), 2.13 (s, 3H), 2.09- 1.95 (m, 1H),1.79-1.55 (m, 5H). 462 45 

(DMSO-d6) 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J = 8.3 Hz, 2H), 5.04 (d, J= 13.1 Hz, 2H), 3.70-3.60 (m, 1H), 3.52-3.36 (m, 2H), 3.22-3.15 (m, 1H),3.07 (dd, J = 22.7, 10.5 Hz, 2H), 2.83-2.73 (m, 1H), 2.66 (d, J = 3.6Hz, 6H), 2.47-2.37 (m, 4H), 2.32-2.13 (m, 8H), 2.03-1.85 (m, 1H),1.72-1.42 (m, 5H) 476 57 

(MeOD) 7.44 (q, J = 8.6 Hz, 4H), 4.27-4.14 (m, 2H), 4.02-3.87 (m, 2H),3.15-3.07 (m, 1H), 2.75 (s, 3H), 2.70 (d, J = 2.8 Hz, 6H), 2.47 (s, 3H),2.31-2.16 (m, 2H). 365 58 

(DMSO-d6) 8.02 (s, 1H), 7.51 (d, J = 7.7 Hz, 2H), 7.41 (d, J = 7.7 Hz,2H), 7.06 (t, J = 7.2 Hz, 2H), 6.56- 6.50 (m, 3H), 5.59 (s, 1H), 4.98(t, J = 10.3 Hz, 2H), 3.34-3.03 (m, 6H), 2.67 (s, 6H), 2.41-2.33 (m,4H), 1.89-1.49 (m, 4H). 484 65 

(DMSO-d6) 7.51 (d, J = 8.2 Hz, 2H), 7.43 (d, J = 8.1 Hz, 2H), 5.01 (d, J= 12.8 Hz, 2H), 3.86 (dd, J = 41.0, 12.2 Hz, 2H), 3.19-3.04 (m, 7H),2.97-2.87 (m, 2H), 2.66 (d, J = 3.2 Hz, 6H), 2.43 (s, 3H), 2.21- 2.14(m, 1H), 1.94-1.87 (m, 2H), 1.67-1.51 (m, 6H), 1.04 (dd, J = 50.8, 10.9Hz, 2H) 488 66 

(MeOD-d4) δ 7.47-7.42 (m, 4H), 5.11 (d, J = 13.2 Hz, 2H), 4.42- 4.35 (m,1H), 3.68-3.64 (m, 2H), 3.06-2.95 (m, 4H), 2.71 (d, J = 11.3 Hz, 6H),2.48 (s, 3H), 2.34 (s, 3H), 2.23 (t, J = 7.4 Hz, 2H), 1.81 (d, J = 12.3Hz, 2H), 1.56 (dd, J = 12.0, 5.0 Hz, 3H), 1.35-1.25 (m, 2H). 462 67 

(DMSO-d6) 7.51 (d, J = 8.2 Hz, 2H), 7.43 (d, J = 8.2 Hz, 2H), 7.30 (dd,J = 7.0, 5.8 Hz, 4H), 7.24-7.20 (m, 1H), 5.02 (t, J = 10.6 Hz, 2H), 4.43(d, J = 13.1 Hz, 1H), 4.08 (d, J = 13.3 Hz, 1H), 3.54 (s, 2H), 3.10 (t,J = 12.0 Hz, 2H), 3.03-2.96 (m, 2H), 2.64 (dd, J = 17.2, 3.8 Hz, 7H),2.44 (d, J = 8.9 Hz, 4H), 2.08 (s, 3H), 1.84-1.59 (m, 6H), 1.44 (dd, J =22.3, 10.8 Hz, 1H), 1.29 (dd, J = 22.4, 11.0 Hz, 1H). 552 68 

(MeOD-d4) 7.27-7.21 (m, 4H), 7.12-7.05 (m, 4H), 7.03-6.98 (m, 1H), 4.97(d, J = 10.4 Hz, 2H), 3.39-3.33 (m, 2H), 3.25-3.12 (m, 3H), 2.98-2.86(m, 3H), 2.64-2.57 (m, 1H), 2.52 (d, J = 13.2 Hz, 6H), 2.42-2.32 (m,1H), 2.27 (s, 3H), 2.19-2.09 (m, 2H), 2.05 (d, J = 8.6 Hz, 3H),1.93-1.79 (m, 1H), 1.63- 1.33 (m, 5H). 552 69 

(DMSO-d6) 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J = 8.3 Hz, 2H), 5.01 (s,2H), 4.36 (d, J = 13.4 Hz, 1H), 4.04 (d, J = 14.0 Hz, 1H), 3.55 (t, J =4.4 Hz, 4H), 3.12-2.94 (m, 4H), 2.66 (d, J = 3.4 Hz, 6H), 2.56 (d, J =6.2 Hz, 1H), 2.45-2.33 (m, 8H), 1.84-1.57 (m, 6H), 1.31 (dd, J = 22.4,10.7 Hz, 1H), 1.16 (dd, J = 21.9, 11.5 Hz, 1H). 518 70 

(DMSO-d6) 7.51 (d, J = 7.4 Hz, 2H), 7.43 (d, J = 7.4 Hz, 2H), 5.04 (d, J= 13.2 Hz, 2H), 3.69-3.42 (m, 6H), 3.24-2.91 (m, 4H), 2.70 (d, J = 35.8Hz, 7H), 2.43-2.24 (m, 10H), 2.02-1.85 (m, 1H), 1.73-1.45 (m, 5H). 51871 

(DMSO-d6) 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J = 8.3 Hz, 2H), 5.03 (d, J= 12.7 Hz, 2H), 3.76 (dd, J = 10.7, 8.4 Hz, 1H), 3.54-3.45 (m, 2H),3.18-3.03 (m, 2H), 2.87-2.82 (m, 2H), 2.79-2.73 (m, 2H), 2.66 (d, J =3.7 Hz, 6H), 2.62-2.53 (m, 2H), 2.43 (s, 3H), 1.71 (d, J = 11.6 Hz, 2H),1.64-1.54 (m, 2H) 460 72 

(DMSO-d6) 7.51 (d, J = 8.3 Hz, 2H), 7.43 (d, J = 8.2 Hz, 2H), 5.03 (d, J= 12.0 Hz, 2H), 3.80-3.70 (m, 1H), 3.52 (dd, J = 12.2, 8.8 Hz, 1H), 3.41(dd, J = 10.8, 4.3 Hz, 2H), 3.19 (dd, J = 12.3, 4.3 Hz, 1H), 3.10-3.03(m, 2H), 2.90-2.82 (m, 2H), 2.80-2.71 (m, 2H), 2.66 (d, J = 4.1 Hz, 6H),2.41 (d, J = 10.6 Hz, 6H), 2.24 (s, 3H), 1.70- 1.55 (m, 4H). 474 73 

(MeOD-d4) 7.44 (t, J = 9.2 Hz, 4H), 5.16 (d, J = 13.2 Hz, 2H), 3.59 (dd,J = 11.6, 5.4 Hz, 6H), 3.52 (t, J = 4.8 Hz, 2H), 3.19-3.12 (m, 2H),3.08-3.01 (m, 1H), 2.72 (dd, J = 12.8, 1.9 Hz, 6H), 2.47 (s, 3H),1.89-1.87 (m, 2H), 1.83-1.69 (m, 6H). 474 74 

(MeOD-d4) 7.44 (t, J = 8.8 Hz, 4H), 5.19 (d, J = 13.3 Hz, 2H), 3.84-3.67(m, 6H), 3.59 (s, 1H), 3.43 (t, J = 7.1 Hz, 1H), 3.19-3.09 (m, 1H),2.89-2.81 (m, 1H), 2.73 (d, J = 13.6 Hz, 6H), 2.48 (s, 3H), 2.27 (t, J =6.9 Hz, 1H), 2.13 (t, J = 7.1 Hz, 1H), 1.83-1.81 (m, 4H). 460 75 

(DMSO-d6) 7.51 (d, J = 7.3 Hz, 2H), 7.43 (d, J = 8.2 Hz, 2H), 5.04 (d, J= 10.7 Hz, 2H), 3.62 (s, 1H), 3.53 (t, J = 6.9 Hz, 1H), 3.33 (s, 1H),3.25 (t, J = 7.0 Hz, 1H), 3.10- 2.98 (m, 6H), 2.77-2.71 (m, 1H), 2.66(d, J = 3.6 Hz, 6H), 2.43 (s, 3H), 2.20 (d, J = 9.3 Hz, 3H), 2.03 (t, J= 6.8 Hz, 1H), 1.91 (t, J = 7.0 Hz, 1H), 1.71 (d, J = 12.9 Hz, 2H),1.64-1.54 (m, 2H). 474 15x

(MeOD-d4) δ 7.47-7.42 (m, 4H), 5.18 (d, J = 13.3 Hz, 2H), 3.21 (t, J =6.9 Hz, 2H), 3.14-3.06 (m, 2H), 2.74 (s, 3H), 2.71 (s, 3H), 2.57- 2.48(m, 10H), 1.89-1.77 (m, 8H), 1.76-1.69 (m, 2H). 476 17x

(DMSO-d6) 7.74 (t, J = 5.5 Hz, 1H), 7.51 (d, J = 8.3 Hz, 2H), 7.44 (d, J= 8.2 Hz, 2H), 5.00 (d, J = 13.0 Hz, 2H), 3.54 (t, J = 4.4 Hz, 4H), 3.14(dd, J = 12.7, 6.5 Hz, 2H), 3.03 (t, J = 11.6 Hz, 2H), 2.66 (d, J = 4.0Hz, 6H), 2.46-2.41 (m, 4H), 2.34-2.29 (m, 6H), 1.74-1.71 (m, 2H), 1.61(qd, J = 12.5, 3.4 Hz, 2H). 478 45x

(DMSO-d6) 7.79 (t, J = 5.6 Hz, 1H), 7.51 (d, J = 8.4 Hz, 2H), 7.43 (d, J= 8.2 Hz, 2H), 4.97 (t, J = 11.7 Hz, 2H), 3.19-2.97 (m, 4H), 2.67 (s,6H), 2.51-2.39 (m, 4H), 2.26-2.19 (m, 2H), 2.10 (s, 6H), 1.85-1.82 (m,1H), 1.72-1.64 (m, 2H), 1.55-1.44 (m, 1H). 436

Compound Nos. 40, 46, 47, 59-62, and 64 were prepared using theappropriate starting materials and reagents according to the sameprocedures as in Example 7.

Example 18 Synthesis of Compound Nos. 40, 46, 47, 59-62, and 64

LCMS Compound ¹H NMR (400 MHz) m/z No. R^(E) (Solvent) δ ppm (M + H) 40

(DMSO-d6) 9.23 (s, 1H), 8.93 (s, 1H), 7.95 (d, J = 8.3 Hz, 2H), 7.43 (d,J = 8.3 Hz, 2H), 5.20 (d, J = 13.0 Hz, 2H), 3.57 (s, 2H), 3.44 (s, 2H),3.23 (t, J = 11.8 Hz, 2H), 3.07-3.01 (m, 1H), 2.40-2.28 (m, 9H),1.78-1.61 (m, 4H), 1.01 (t, J = 7.1 Hz, 3H). 434 46

(MeOD-d4) 8.87 (s, 1H), 8.81 (s, 1H), 7.81 (d, J = 8.4 Hz, 2H), 7.35 (d,J = 8.3 Hz, 2H), 5.31 (d, J = 13.3 Hz, 2H), 3.33 (t, J = 4.9 Hz, 2H),3.23-3.16 (m, 2H), 2.63-2.55 (m, 1H), 2.46 (t, J = 6.9 Hz, 2H), 2.41 (s,3H), 2.27 (s, 6H), 1.96-1.76 (m, 4H). 408 47

(MeOD-d4) 8.91 (s, 1H), 8.83 (s, 1H), 7.85 (d, J = 8.3 Hz, 2H), 7.38 (d,J = 8.2 Hz, 2H), 5.19 (t, J = 10.9 Hz, 2H), 3.43-3.26 (m, 2H), 2.61-2.52(m, 1H), 2.43 (d, J = 9.5 Hz, 5H), 2.31-2.24 (m, 8H), 2.02- 1.85 (m,3H), 1.72-1.62 (m, 1H). 408 59

(MeOD-d4) 8.95 (s, 1H), 8.86 (s, 1H), 7.88 (d, J = 8.5 Hz, 2H), 7.41 (d,J = 8.2 Hz, 2H), 5.35 (t, J = 12.9 Hz, 2H), 4.61 (d, J = 13.3 Hz, 1H),4.25 (d, J = 13.7 Hz, 1H), 3.27-3.11 (m, 4H), 2.89-2.84 (m, 1H),2.67-2.57 (m, 5H), 2.44 (s, 3H), 1.99-1.82 (m, 6H), 1.54-1.44 (m, 1H),1.41-1.31 (m, 1H), 1.09 (t, J = 7.2 Hz, 6H). 476 60

(DMSO-d6) 9.22 (s, 1H), 8.93 (d, J = 0.8 Hz, 1H), 7.95 (d, J = 8.2 Hz,2H), 7.43 (d, J = 8.3 Hz, 2H), 5.23 (d, J = 12.7 Hz, 2H), 3.74- 3.64 (m,1H), 3.53- 3.33 (m, 2H), 3.26-3.17 (m, 3H), 2.88-2.80 (m, 1H), 2.42-2.27(m, 4H), 2.24-2.10 (m, 8H), 2.05-1.86 (m, 1H), 1.81-1.44 (m, 5H). 448 61

(MeOD-d4) 8.86 (s, 1H), 8.76 (s, 1H), 7.81 (d, J = 8.5 Hz, 2H), 7.34 (d,J = 8.2 Hz, 2H), 5.24 (d, J = 13.2 Hz, 2H), 3.28-3.25 (m, 2H), 3.09 (t,J = 11.8 Hz, 2H), 2.40 (dd, J = 13.7, 6.9 Hz, 5H), 2.21 (d, J = 11.9 Hz,8H), 1.83 (d, J = 12.4 Hz, 2H), 1.61-1.52 (m, 3H), 1.34-1.24 (m, 2H).436 62

(MeOD-d4) 8.86 (s, 1H), 8.80 (s, 1H), 7.80 (d, J = 8.5 Hz, 2H), 7.34 (d,J = 8.2 Hz, 2H), 5.30 (d, J = 13.3 Hz, 2H), 4.39 (p, J = 7.1 Hz, 1H),3.67 (td, J = 7.1, 1.6 Hz, 2H), 3.22-3.15 (m, 2H), 3.01 (td, J = 7.1,1.6 Hz, 2H), 2.58 (tt, J = 11.3, 4.0 Hz, 1H), 2.40 (s, 3H), 2.35 (s,3H), 1.92-1.77 (m, 4H). 406 64

(DMSO-d6) 9.22 (s, 1H), 8.93 (s, 1H), 7.95 (d, J = 8.5 Hz, 2H), 7.77 (t,J = 5.7 Hz, 1H), 7.43 (d, J = 8.2 Hz, 2H), 5.18 (d, J = 13.2 Hz, 2H),3.55 (t, J = 4.4 Hz, 4H), 3.22-3.13 (m, 4H), 2.40-2.31 (m, 10H), 1.81(dd, J = 13.1, 1.9 Hz, 2H), 1.72-1.62 (m, 2H). 450

BIOLOGICAL EXAMPLES Example B1—Inhibition of Human TLR7 in HumanPlasmacytoid Dendritic Cells

Inhibition of human TLR7 was tested using human plasmacytoid dendriticcells. When placed in cell culture, engagement of TLR7 with an agonistleads to expression and release of cytokines into the media. Antagonist(inhibitory) activity indicates that test compounds can permeate intointact cells.

Materials:

Buffy coats from anonymized, healthy human donors. CD304(BDCA-4/Neuropilin-1) MicroBead Kit (Milteny Cat. No. 130-090-532). Heatinactivated influenza virus (ATCC Cat No. VR-95). Human interferon-alphaELISA kit (Mabtech Cat. No. 3425-1H-20).

Assay Procedures:

Human plasmacytoid dendritic cells were plated into 96 well plates atapproximately 30,000 cells per well. Test compounds were seriallydiluted and added to the plates. Immediately after adding testcompounds, the TLR7 agonist (heat inactivated influenza virus) was addedto a final multiplicity of infection of 2. Cells were incubated for 24hours at 37° C. A portion of the media supernatant was analyzed for thepresence of interferon-alpha using an ELISA kit. The amount ofinterferon-alpha produced is a reflection of the amount ofTLR7-dependent receptor activity. The IC₅₀ values (the concentration atwhich 50% of the TLR7-dependent receptor activity is reduced) werecalculated based upon the TLR7-dependent receptor activity over a rangeof different test compound concentrations. Selected compounds of thepresent invention were tested and the activities (IC₅₀) are summarizedin Table B1-1.

TABLE B1-1 Compound No. Human TLR7 IC₅₀ (μM) 1 2.967 2 9.934 4 3.36 52.23 6 >10 9 >10 2-1 >10

Example B2—Inhibition of Human TLR8 in Human Monocytes

Inhibition of human TLR8 was demonstrated using human monocytes. Whenplaced in cell culture, engagement of TLR8 with an agonist leads toexpression and release of cytokines into the media. Antagonist(inhibitory) activity indicates that test compounds can permeate intointact cells.

Materials:

Buffy coats from anonymized, healthy human donors. CD14 microbeads(Milteny Cat. No. 130-050-201). TLR8 agonist,(5′-M2UGCUGCUUGUG-/glycerol/-GUGUUCGUCGUM2-5′ with M2=C6-linker, ORN8L,RNA oligonucleotide (Chem Genes Corp.). Human TNF-alpha ELISA kit(Mabtech Cat. No. 3510-1H-20). Human interleukin (IL)-1 beta ELISA kit(Mabtech Cat. No. 3415-1H-20).

Assay Procedures:

Following isolation of monocytes from buffy coats, human monocytes wereplated into 96 well plates at approximately 200,000 cells per well. Testcompounds were serially diluted and added to the plates. Immediatelyafter adding test compounds, the TLR8 agonist (ORN8L, RNAoligonucleotide) was added to a final concentration of 100 μg/mL. Cellswere incubated for 24 hours at 37° C. A portion of the media supernatantwas analyzed for the presence of TNF-alpha and/or IL-1 beta using ELISAkits. The amount of TNF-alpha or IL-1 beta produced is a reflection ofthe amount of TLR8-dependent receptor activity. The IC₅₀ values (theconcentration at which 50% of the TLR8-dependent receptor activity isreduced) were calculated based upon the TLR8-dependent receptor activityover a range of different test compound concentrations. Selectedcompounds of the present invention were tested and the activities (IC₅₀)are summarized in Table B2-1.

TABLE B2-1 Human TLR8 IC₅₀ (μM) Compound No. TNF-a IL-1b  1 0.62 0.74  20.67 0.90  3 >10 >10  4 0.77 1.01  5 >10 >10  6 6.68 >10  7 >10 >10 8 >10 >10  9 1.22 5.02 11 >10 >10 12a >10 >10 13* >10 >10 15 >10 >1016* 20 NT 17* >10 >10 18 >10 >10 22 >10 >10 23 20 NT 24 20 NT 25 20 NT27 20 NT 29 >10 1.61 31 2.68 NT 32 >10 >10 34 20 NT 35 20 NT 36 7.68 NT38 20 NT 40 0.226 NT 41 20 NT 42 20 NT 43 20 NT 44* 20 NT 45* 20 NT 4620 NT 47* 2.616 NT 48 20 NT 53 20 NT  7x >10 >10  9x >10 >10 15x 4.6 NT17x 20 NT 19x 0.74 0.74 20x 4.86 5.04 21x >10 >10 24x* >10 >10 25x 4.854.54 31x >10 >10 32x >10 >10 33x* >10 >10 45x* 20 NT 49x* 3.56 3.94 51x0.23 0.33 54x* 0.29 0.74 59x 2.04 2.11 63x* 1.12 1.01 64x 0.90 0.66 2-19.77 9.92 2-2 20 NT 2-3 >10 >10 2-4 >10 >10 2-5 >10 >10 2-6 >10 >102-12 >10 >10 *Denotes compounds that were tested as racemic mixtures. NT= not tested

Additional selected compounds of the present invention were tested andthe activities (IC₅₀) are summarized in Table B2-1A.

TABLE B2-1A Human TLR8 IC₅₀ (μM) Compound No. TNF-a IL-1b 57* 20 NT 58*20 NT 59 0.77 NT 60* 0.98 NT 61 4.85 NT 62 3.84 NT 63 20 NT 64 20 NT 651.85 NT 66 20.00 NT 67 0.48 NT 68* 1.18 NT 69 3.84 NT 70* 5.12 NT 71 20NT 72 9.17 NT 73 20 NT 74 20 NT 75 20 NT 76 11.73 NT *Denotes compoundsthat were tested as racemic mixtures. NT = not tested

Example B3—Inhibition of Human TLR9 in Human B Cells

Inhibition of human TLR9 was demonstrated using human B cells. Whenplaced in cell culture, engagement of TLR9 with an agonist leads toexpression and release of cytokines into the media. Antagonist(inhibitory) activity indicates that test compounds can permeate intointact cells.

Materials:

Buffy coats from anonymized, healthy human donors. CD19 microbeads(Miltenyi Cat. No. 130-050-301). TLR9 agonist, 1018 ISS, CpG-containingDNA oligonucleotide. Human interleukin (IL)-6 ELISA kit (Mabtech Cat.No. 3460-1H-20).

Assay Procedures:

Following isolation of monocytes from buffy coats, human B cells wereplated into 96 well plates at approximately 300,000 cells per well. Testcompounds were serially diluted and added to the plates. Test compoundswere typically assayed using a concentration range from about 0.01 μM toabout 10 μM. Certain test compounds were further assayed in an expandeddilution series using a compound concentration range from about 0.001 μMto about 30 μM. Immediately after adding test compounds, the TLR9agonist (1018 ISS, CpG-containing DNA oligonucleotide) was added to afinal concentration of 1 μM. Cells were incubated for 48 hours at 37° C.A portion of the media supernatant was analyzed for the presence of IL-6using ELISA kits. The amount of IL-6 produced is a reflection of theamount of TLR9-dependent receptor activity. The IC₅₀ values (theconcentration at which 50% of the TLR9-dependent receptor activity isreduced) were calculated based upon the TLR9-dependent receptor activityover a range of different test compound concentrations.

Selected compounds of the present invention were tested and theactivities (IC₅₀) are summarized in Table B3-1.

TABLE B3-1 Compound No. Human TLR9 IC₅₀ (μM)  1 0.040  2 0.242  3 0.143 4 0.093  5 0.040  6 0.154  7 0.360  8 0.308  9 0.003 11 0.379 12a 0.07113* 0.292 15 0.250 16* 0.046 17* 0.083 18 0.137 20 0.018; 0.024** 220.031 23 >10 24 0.400 25 >10 27 >10 29 0.007 31 0.086 32 0.055 34 0.25135 3.710 36 1.150 38 0.040 40 0.026 41 0.793 42 0.133 43 0.001; 0.013**44* 0.202 45* 0.001; 0.014** 46 0.002; 0.01**  47* 0.027 48 10.800 532.228 55 0.007; 0.009**  7x 0.368  9x 0.040 15x 0.408 17x 0.017 19x0.018 20x 0.003 21x 0.004 24x* 0.032 25x 0.041 31x 0.211 32x 0.341 33x*0.070 45x* 0.009 49x* 0.029 51x 0.006 54x* 0.004 59x 0.059 63x* 0.01864x 0.013 2-1 4.647 2-2 3.770 2-3 >10 2-4 >10 2-5 >10 2-6 >10 2-12 0.427*Denotes compounds that were tested as racemic mixtures. **Denotes datafrom expanded dilution series.

Additional selected compounds of the present invention were tested andthe activities (IC₅₀) are summarized in Table B3-1A.

TABLE B3-1A Compound No. Human TLR9 IC₅₀ (μM) 57* 9.373 58* 4.818 590.006 60* 0.002 61 0.009 62 0.021 63 5.580 64 0.557 65 0.010 66 0.182 670.049 68* 0.085 69 0.253 70* 0.150 71 0.588 72 0.012 73 1.141 74 2.58975 0.025 76 0.118 *Denotes compounds that were tested as racemicmixtures.

Example B4—Inhibition of Mouse TLR9 in Mouse Acute Challenge Model

Inhibition of mouse TLR9 was demonstrated in vivo using an acutechallenge model in mice. When administered a CpG-containing DNAoligonucleotide, mice respond in an acute manner with release ofcytokines into the peripheral blood within 6 hours. The addition of aninhibitor against TLR9 will attenuate the response to the DNAoligonucleotide agonist, which can be measured through a reduction inserum cytokines. Demonstration of antagonist (inhibitory) activityindicates that test compounds can distribute systemically, are stable inblood and are not immediately metabolized to inactive metabolites.Additionally, antagonist (inhibitory) activity indicates that testcompounds can permeate intact cells.

Materials:

Balb/c mice (Charles River). TLR9 agonist 1018 ISS, CpG-containing DNAoligonucleotide. Mouse interleukin (IL)-12p40 ELISA kit (BD PharmingenCat. No. 551219 and 554476).

Assay Procedures:

Mice were injected by the intravenous or intra-peritoneal routes withtest compound at 5 mg/kg. Following injection of test compound, micewere injected with a TLR9 agonist (a CpG-containing DNA oligonucleotide)by the intra-peritoneal route to a final dose of approximately 2.5mg/kg. Four hours following administration of the DNA oligonucleotide,blood was collected and processed to serum. The serum was tested for thepresence of IL-12 using an ELISA kit. The amount of IL-12 produced is areflection of the amount of TLR9-dependent receptor activity. Theactivity of the test compound, presented as percent inhibition ofagonist alone, is presented in FIG. 1.

Example B4-a—Inhibition of Mouse TLR9 in Mouse Acute Challenge ModelOver Time

Inhibition of mouse TLR9 over a 24 hour time period was demonstrated invivo using an acute challenge model in mice. When administered aCpG-containing DNA oligonucleotide, mice respond in an acute manner withrelease of cytokines into the peripheral blood within 6 hours. Theaddition of an inhibitor against TLR9 will attenuate the response to theDNA oligonucleotide agonist, which can be measured through a reductionin serum cytokines. Demonstration of antagonist (inhibitory) activityindicates that test compounds can distribute systemically, are stable inblood and are not immediately metabolized to inactive metabolites.Additionally, antagonist (inhibitory) activity indicates that testcompounds can permeate intact cells.

Materials:

Balb/c mice (Charles River). TLR9 agonist 1018 ISS, CpG-containing DNAoligonucleotide. Mouse interleukin (IL)-12p40 ELISA kit (BD PharmingenCat. No. 551219 and 554476).

Assay Procedures:

Mice were injected by the intra-peritoneal dosing route with testcompound at 5 mg/kg. Following injection of test compound, mice wereinjected with a TLR9 agonist (a CpG-containing DNA oligonucleotide) bythe intra-peritoneal route to a final dose of approximately 2.5 mg/kg.Two, four and twenty-four hours following administration of the DNAoligonucleotide, blood was collected from mice and processed to serum.The serum was tested for the presence of IL-12 using an ELISA kit. Theamount of IL-12 produced is a reflection of the amount of TLR9-dependentreceptor activity. The activity of the test compound, presented aspercent inhibition of agonist alone, is presented in FIG. 2.

Example B5—Receptor Specificity

Representative compounds were tested for antagonist activity againstrelated toll-like receptor family members and other nucleic acidintracellular signaling receptors in primary human leukocytes. Thecompounds were Compound Nos. 5 and 9, and they were tested for theirability to inhibit human RIG-I, TLR-2, TLR-4, and TLR-5. With oneexception, neither compound was able to inhibit these receptors greaterthan 50% at 10 μM. The one exception was Compound No. 9, which had anIC50 of 8.3 μM against RIG-I.

Example B6—Plasma Stability

The stability of compounds in human plasma was tested. Human plasma wasspiked with compound to final concentration of 90% plasma and 2 μMcompound. Samples were incubated for 0, 5, 15, 30, 45 and 60 minutes at37° C. The reaction was stopped by the addition of acetonitrile. Analiquot of the stopped reaction was mixed with ultra-pure water(Millipore, ZMQS50F01) and analyzed by liquidchromatography/electrospray ionization mass spectroscopy. Selectedcompounds of the present invention were tested and the stability valuesare summarized in Table B6-1.

TABLE B6-1 Compound No. T_(1/2) (minute) 1 224.4 3 207.0 5 1071.0

Example B7—Metabolic Stability

The stability of compounds in human liver microsomes was tested. Humanliver microsomes (from BD Gentest) were spiked with compounds to a finalliver microsomal protein concentration of 0.5 mg/mL and a final compoundconcentration of 1.5 μM. Samples were incubated for 0, 5, 15, 30, 45minutes at 37° C. The reaction was stopped by the addition ofacetonitrile. An aliquot of the stopped reaction was mixed withultra-pure water (Millipore, ZMQS50F01) and analyzed by liquidchromatography/electrospray ionization mass spectroscopy. Selectedcompounds of the present invention were tested and the stability valuesare summarized in Table B7-1.

TABLE B7-1 Compound No. T_(1/2) (minute) Cl_(int) (mL/min/kg) 1 5.0347.0 3 383.8 4.5 5 800.9 2.2

All references throughout, such as publications, patents, patentapplications and published patent applications, are incorporated hereinby reference in their entireties.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity ofunderstanding, it is apparent to those skilled in the art that certainminor changes and modifications will be practiced. Therefore, thedescription and examples should not be construed as limiting the scopeof the invention.

1. A compound of formula (I):

or a salt or solvate thereof, wherein: A¹ is C or N; A² is CR², N orNR^(2a); A³ is CR³⁰, N or NR^(3a); A⁴ is N or CR⁴; A⁵ is N or CR⁵;provided that two, three or four of A¹, A², A³, A⁴ and A⁵ are N; whereinthe dashed lines indicate partial or delocalized bonds in an aromaticring; i and j are independently 0, 1 or 2; R¹ is C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or 3-12-memberedheterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A); each R², R³, R³⁰, R⁴and R⁵ is independently hydrogen, halogen, C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or 3-12-memberedheterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A); each R^(2a) and R^(3a)is independently hydrogen, C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl or 3-12-membered heterocyclyl; wherein theC₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl and3-12-membered heterocyclyl are independently optionally substituted byR^(10A); each R⁶, where present, is independently C₁-C₆ alkyl optionallysubstituted by R^(10A); n is 0, 1, 2, 3 or 4; U is a bond or methyleneoptionally substituted by R¹⁰; V is a bond or C₁-C₂ alkylene optionallysubstituted by R¹⁰; W is a bond or C₁-C₄ alkylene optionally substitutedby one or both of R^(W1) and R^(W2); X is —CR^(X1)R^(X2)—; Y is—CR^(Y1)R^(Y2)—; R⁷ is hydrogen, C₁-C₆ alkyl, or taken together with R⁸to form an ethylene optionally substituted by R¹⁰, or taken togetherwith R^(Y1), R^(X1) or R^(W1), where present, to form a C₁-C₆ alkyleneoptionally substituted by R¹⁰; R⁸ is hydrogen, C₁-C₆ alkyl optionallysubstituted by R¹⁰, C₆-C₁₄ aryl, 5-10-membered heteroaryl, or takentogether with R⁷ to form an ethylene optionally substituted by R¹⁰, ortaken together with R^(Y1), R^(Y2), R^(X1), R^(X2), or R^(W1), wherepresent, to form a C₁-C₆ alkylene optionally substituted by R¹⁰, ortaken together with R¹⁰, where present, to form a C₁-C₆ alkylene, ortaken together with R⁹ and the nitrogen atom to which they are attachedto form a 3-12-membered heterocyclyl optionally substituted by R¹⁰ or a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(Y1), R^(Y2), R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R^(X1), R^(X2), R^(Y1), R^(Y2), R⁹ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(W1), R^(W2),where present, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁹ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰; R⁹ is hydrogen, C₁-C₆ alkyl optionally substitutedby R¹⁰, or taken together with R⁸ and the nitrogen atom to which theyare attached to form a 3-12-membered heterocyclyl optionally substitutedby R¹⁰ or a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(Y1), R^(Y2), R⁸ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(W1), R^(W2),where present, R^(X)1, R^(X2), R^(Y1), R^(Y2), R⁸ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰; R^(W1), where present, is C₁-C₆ alkyl optionallysubstituted by R^(10A), or taken together with R⁷, R⁸, R^(X1) or R^(Y1)to form a C₁-C₆ alkylene optionally substituted by R¹⁰, or takentogether with R^(W2), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰; R^(W2), where present, is C₁-C₆ alkyloptionally substituted by R^(10A), or taken together with R^(W1),R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰; R^(X1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A),or taken together with R⁷, R⁸, R^(Y1) or R^(W1), where present, to forma C₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attachedto form a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(W1), R^(W2), where present, R^(X2), R^(Y1),R^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰; R^(X2) ishydrogen or C₁-C₆ alkyl optionally substituted by R^(10A), or takentogether with R^(X1), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R⁸ to form a C₁-C₆ alkylene optionally substituted by R¹⁰;R^(Y1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R⁷, R⁸, R^(X1) or R^(W1), where present, to form aC₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(X1), R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰; R^(Y2) ishydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), or takentogether with R^(Y1)R⁸, R⁹ and the atoms to which they are attached toform a 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(X1), R^(X2), R^(Y1), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(X2), R^(Y1), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R⁸ to form a C₁-C₆ alkylene optionally substituted by R¹⁰;each R¹⁰ is independently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl,C₃-C₈ cycloalkyl, 3-12-membered heterocyclyl, 5-10-membered heteroaryl,C₆-C₁₄ aryl, halogen, —CN, —OR¹¹, —SR¹¹, —NR¹²R¹³, —NO₂, —C═NH(OR¹¹),—C(O)R¹¹, —OC(O)R¹, —C(O)OR¹¹, —C(O)NR¹²R¹³, —NR¹¹C(O)R¹²,—NR¹¹C(O)OR¹², —NR¹¹C(O)NR¹²R¹³, —S(O)R¹¹, —S(O)₂R¹¹, —NR¹¹S(O)R¹²,—NR¹¹S(O)₂R¹², —S(O)NR¹²R¹³, —S(O)₂NR¹²R¹³, or —P(O)(OR¹²⁾ (OR¹³);wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl,3-12-membered heterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl ofR¹⁰ are independently optionally substituted by halogen, —CN, oxo,—OR¹⁴, —SR¹⁴, —NR¹⁴R¹⁵, —C(O)R¹⁴, —C(O)OR¹⁴, —S(O)R¹⁴, —S(O)₂R¹⁴,—P(O)(OR¹⁴)(OR⁵), 3-12-membered heterocyclyl, 5-10-membered heteroaryl,C₆-C₁₄ aryl, C₃-C₈ cycloalkyl, or C₁-C₆ alkyl optionally substituted byoxo, —OH or halogen, or taken together with R⁸ to form a C₁-C₆ alkylene;each R^(10A) is independently oxo or R¹⁰; R¹¹ is independently hydrogen,C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄aryl, 5-6-membered heteroaryl or 3-6-membered heterocyclyl, wherein theC₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄aryl, 5-6-membered heteroaryl and 3-6-membered heterocyclyl of R¹ areindependently optionally substituted by halogen, oxo, —CN, —OR¹⁶,—NR¹⁶R¹⁷, —P(O)(OR¹⁶ (OR¹⁷), or C₁-C₆ alkyl optionally substituted byhalogen, —OH or oxo; R¹² and R¹³ are each independently hydrogen, C₁-C₆alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl,5-6-membered heteroaryl or 3-6 membered heterocyclyl, wherein the C₁-C₆alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl,5-6-membered heteroaryl and 3-6 membered heterocyclyl of R¹² and R¹³ areindependently optionally substituted by halogen, oxo, —CN, —OR¹⁶,—NR¹⁶R¹⁷ or C₁-C₆ alkyl optionally substituted by halogen, —OH or oxo;or R¹² and R¹³ are taken together with the atom to which they attachedto form a 3-6 membered heterocyclyl optionally substituted by halogen,oxo, —OR¹⁶, —NR¹⁶R¹⁷ or C₁-C₆ alkyl optionally substituted by halogen,oxo or —OH; R¹⁴ and R¹⁵ are each independently hydrogen, C₁-C₆ alkyloptionally substituted by halogen or oxo, C₂-C₆ alkenyl optionallysubstituted by halogen or oxo, or C₂-C₆ alkynyl optionally substitutedby halogen or oxo; or R¹⁴ and R¹⁵ are taken together with the atom towhich they attached to form a 3-6 membered heterocyclyl optionallysubstituted by halogen, oxo or C₁-C₆ alkyl optionally substituted byhalogen or oxo; and R¹⁶ and R¹⁷ are each independently hydrogen, C₁-C₆alkyl optionally substituted by halogen or oxo, C₂-C₆ alkenyl optionallysubstituted by halogen or oxo, or C₂-C₆ alkynyl optionally substitutedby halogen or oxo; or R¹⁶ and R¹⁷ are taken together with the atom towhich they attached to form a 3-6 membered heterocyclyl optionallysubstituted by halogen, oxo or C₁-C₆ alkyl optionally substituted by oxoor halogen; provided that when R⁸ and R⁹ are taken together with thenitrogen atom to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, and the 5-10-memberedheteroaryl is a fused ring heteroaryl comprising an aryl moiety fused toa heterocycle containing the nitrogen atom to which R⁸ and R⁹ areattached, the aryl moiety is not adjacent to the nitrogen atom to whichR⁸ and R⁹ are attached; and provided that the compounds is other thanCompound Nos. 1x-83x in Table 1X and salts thereof.
 2. The compound ofclaim 1, or a salt or solvate thereof, wherein A¹ is N, A² is CR² and A³is N.
 3. The compound of claim 1, or a salt or solvate thereof, whereinA¹ is C, A² is CR² or NR^(2a) and A³ is NH.
 4. The compound of claim 3,or a salt or solvate thereof, wherein R^(2a) is C₁-C₆ alkyl.
 5. Thecompound of any one of claims 1 to 4, or a salt or solvate thereof,wherein A⁴ is N and A⁵ is N.
 6. The compound of any one of claims 1 to4, or a salt or solvate thereof, wherein A⁴ is N and A⁵ is CR⁵.
 7. Thecompound of any one of claims 1 to 4, or a salt or solvate thereof,wherein A⁴ is CR⁴ and A⁵ is CR⁵.
 8. The compound of claim 7, or a saltor solvate thereof, wherein R⁴ is hydrogen.
 9. The compound of any oneof claims 6 to 8, or a salt or solvate thereof, wherein R⁵ is hydrogen.10. The compound of claim 1, or a salt or solvate thereof, wherein thecompound is of the formula (Ia):

or a salt or solvate thereof.
 11. The compound of any one of claims 1 to10, or a salt or solvate thereof, wherein i is 2 and j is 1 or
 2. 12.The compound of any one of claims 1 to 10, or a salt or solvate thereof,wherein i is 1 and j is
 2. 13. The compound of any one of claims 1 to10, or a salt or solvate thereof, wherein i is 1 and j is
 1. 14. Thecompound of any one of claims 1 to 10, or a salt or solvate thereof,wherein i is 1 and j is
 0. 15. The compound of any one of claims 1 to10, or a salt or solvate thereof, wherein i is 0 and j is
 0. 16. Thecompound of claim 1, or a salt or solvate thereof, wherein the compoundis of the formula (II):

or a salt or solvate thereof.
 17. The compound of claim 1, or a salt orsolvate thereof, wherein the compound is of the formula (IIa):

or a salt or solvate thereof.
 18. The compound of any one of claims 1 to17, or a salt or solvate thereof, wherein U is a bond.
 19. The compoundof any one of claims 1 to 18, or a salt or solvate thereof, wherein V isa bond.
 20. The compound of any one of claims 1 to 18, or a salt orsolvate thereof, wherein V is ethylene (—CH₂CH₂—).
 21. The compound ofclaim 1, or a salt or solvate thereof, wherein the compound is of theformula (III):

or a salt or solvate thereof.
 22. The compound of claim 1, or a salt orsolvate thereof, wherein the compound is of the formula (IIIa):

or a salt or solvate thereof.
 23. The compound of any one of claims 1 to22, or a salt or solvate thereof, wherein n is
 0. 24. The compound ofany one of claims 1 to 22, or a salt or solvate thereof, wherein n is 1or 2, and each R⁶ is independently C₁-C₆ alkyl optionally substituted byR^(10A).
 25. The compound of any one of claims 1 to 22, or a salt orsolvate thereof, wherein n is 1 and R⁶ is C₁-C₆ alkyl.
 26. The compoundof any one of claims 1 to 25, or a salt or solvate thereof, wherein R¹is phenyl optionally substituted by R^(10A).
 27. The compound of claim26, or a salt or solvate thereof, wherein R¹ is phenyl optionallysubstituted by C₁-C₆ alkyl or halo.
 28. The compound of claim 27, or asalt or solvate thereof, wherein R¹ is 4-methylphenyl or 4-chlorophenyl.29. The compound of any one of claims 1 to 28, or a salt or solvatethereof, wherein R² is C₁-C₆ alkyl.
 30. The compound of claim 29, or asalt or solvate thereof, wherein R² is methyl.
 31. The compound of anyone of claims 1 to 30, or a salt or solvate thereof, wherein R³ is C₁-C₆alkyl.
 32. The compound of claim 31, or a salt or solvate thereof,wherein R³ is methyl.
 33. The compound of any one of claims 1 to 32, ora salt or solvate thereof, wherein R⁷ is hydrogen or C₁-C₆ alkyl. 34.The compound of claim 33, or a salt or solvate thereof, wherein R⁷ ishydrogen.
 35. The compound of any one of claims 1 to 34, or a salt orsolvate thereof, wherein W is a bond.
 36. The compound of any one ofclaims 1 to 34, or a salt or solvate thereof, wherein W is C₁-C₄alkylene optionally substituted by one or both of R^(W1) and R^(W2). 37.The compound of claim 36, or a salt or solvate thereof, wherein W isC₁-C₄ alkylene.
 38. The compound of claim 36, or a salt or solvatethereof, wherein W is methylene optionally substituted by one or both ofR^(W1) and R^(W2).
 39. The compound of any one of claims 1 to 38, or asalt or solvate thereof, wherein each of R^(X1) and R^(X2) isindependently hydrogen or C₁-C₆ alkyl.
 40. The compound of claim 39, ora salt or solvate thereof, wherein each of R^(X1) and R^(X2) ishydrogen.
 41. The compound of claim 39, or a salt or solvate thereof,wherein each of R^(X1) and R^(X2) is C1-C₆ alkyl.
 42. The compound ofany one of claims 1 to 41, or a salt or solvate thereof, wherein each ofR^(Y1) and R^(Y2) is independently hydrogen or C₁-C₆ alkyl.
 43. Thecompound of claim 42, or a salt or solvate thereof, wherein each ofR^(Y1) and R^(Y2) is hydrogen.
 44. The compound of any one of claims 1to 43, or a salt or solvate thereof, wherein R⁸ is hydrogen or C₁-C₆alkyl.
 45. The compound of claim 44, or a salt or solvate thereof,wherein R⁸ is hydrogen.
 46. The compound of claim 44, or a salt orsolvate thereof, wherein R⁸ is C₁-C₆ alkyl.
 47. The compound of any oneof claims 1 to 46, or a salt or solvate thereof, wherein R⁹ is hydrogenor C₁-C₆ alkyl optionally substituted by R¹⁰.
 48. The compound of claim47, or a salt or solvate thereof, wherein R⁹ is C₁-C₆ alkyl.
 49. Thecompound of claim 47, or a salt or solvate thereof, wherein R⁹ is C₁-C₆alkyl substituted by phenyl.
 50. The compound of any one of claims 1 to43, or a salt or solvate thereof, wherein R⁸ and R⁹ are taken togetherwith the nitrogen atom to which they are attached to form a3-12-membered heterocyclyl optionally substituted by R¹⁰ or a5-10-membered heteroaryl optionally substituted by R¹⁰.
 51. The compoundof claim 50, or a salt or solvate thereof, wherein R⁸ and R⁹ are takentogether with the nitrogen atom to which they are attached to form a3-12-membered heterocyclyl optionally substituted by R¹⁰.
 52. Thecompound of claim 51, or a salt or solvate thereof, wherein R⁸ and R⁹are taken together with the nitrogen atom to which they are attached toform a 3-7-membered heterocyclyl optionally substituted by R¹⁰.
 53. Thecompound of claim 52, or a salt or solvate thereof, wherein the3-7-membered heterocyclyl is selected from the group consisting ofazetidinyl, pyrrolidinyl and morpholinyl.
 54. The compound of claim 50,or a salt or solvate thereof, wherein R⁸ and R⁹ are taken together withthe nitrogen atom to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰.
 55. The compound of any one ofclaims 1 to 41, or a salt or solvate thereof, wherein R^(Y1), R^(Y2), R⁸and R⁹ are taken together with the atoms to which they are attached toform a 5-10-membered heteroaryl optionally substituted by R¹⁰.
 56. Thecompound of claim 55, or a salt or solvate thereof, wherein R^(Y1),R^(Y2), R⁸ and R⁹ are taken together with the atoms to which they areattached to form a 5-6-membered heteroaryl optionally substituted byR¹⁰.
 57. The compound of claim 56, or a salt or solvate thereof, whereinthe 5-6-membered heteroaryl is imidazol-4-yl.
 58. The compound of anyone of claims 1 to 38, or a salt or solvate thereof, wherein R^(X1) andR⁸ are taken together to form a methylene (—CH₂—).
 59. The compound ofany one of claims 1 to 38, or a salt or solvate thereof, wherein R^(Y1)and R⁸ are taken together to form a propylene (—CH₂CH₂CH₂—).
 60. Thecompound of claim 58 or 59, or a salt or solvate thereof, wherein R⁹ isC₁-C₆ alkyl optionally substituted by phenyl.
 61. The compound of anyone of claims 1 to 38, or a salt or solvate thereof, wherein R^(X1),R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ are taken together with the atoms towhich they are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰.
 62. The compound of claim 36, or a salt or solvatethereof, wherein W is C₁-C₄ alkylene substituted by R^(W1) and R^(W2),and R^(W1), R^(W2), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ are takentogether with the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰.
 63. The compoundof claim 36, or a salt or solvate thereof, wherein W is C₁-C₄ alkylenesubstituted by R^(W1) and optionally substituted R^(W2).
 64. Thecompound of claim 63, or a salt or solvate thereof, W is methylenesubstituted by R^(W1).
 65. The compound of claim 63 or 64, or a salt orsolvate thereof, wherein R^(W1) and R⁸ are taken together to form amethylene (—CH₂—) or ethylene (—CH₂CH₂—).
 66. The compound of claim 63or 64, or a salt or solvate thereof, wherein R^(W1) and R^(Y1) are takentogether to form a methylene (—CH₂—).
 67. The compound of any one ofclaims 1 to 32, or a salt or solvate thereof, wherein R⁷ and R⁸ aretaken together to form an ethylene optionally substituted by R¹⁰. 68.The compound of claim 67, or a salt or solvate thereof, wherein W is abond.
 69. The compound of claim 67 or 68, or a salt or solvate thereof,wherein R⁹ is C₁-C₆ alkyl optionally substituted by R¹⁰.
 70. Thecompound of any one of claims 1 to 32, or a salt or solvate thereof,wherein the —N(R⁷)—W—X—Y—N(R⁸)R⁹ moiety is selected from the groupconsisting of:


71. The compound of claim 1, or a salt or solvate thereof, wherein thecompound is of the formula (IIa-1a-2):

or a salt or solvate thereof.
 72. The compound of claim 71, or a salt orsolvate thereof, wherein V is a bond.
 73. The compound of claim 71, or asalt or solvate thereof, wherein V is C₁-C₂ alkylene.
 74. The compoundof any one of claims 71 to 73, or a salt or solvate thereof, wherein R²and R³ are independently hydrogen or C₁-C₆ alkyl.
 75. The compound ofclaim 74, or a salt or solvate thereof, wherein R² and R³ areindependently hydrogen or methyl.
 76. The compound of any one of claims71 to 75, or a salt or solvate thereof, wherein k is 1 or
 2. 77. Thecompound of any one of claims 71 to 76, or a salt or solvate thereof,wherein n is 1 and R⁶ is C₁-C₆ alkyl.
 78. The compound of claim 77, or asalt or solvate thereof, wherein R⁶ is methyl.
 79. The compound of anyone of claims 71 to 76, or a salt or solvate thereof, wherein n is 0.80. The compound of any one of claims 71 to 79, or a salt or solvatethereof, wherein R⁸ and R⁹ are independently C₁-C₆ alkyl optionallysubstituted by R¹⁰.
 81. The compound of claim 80, or a salt or solvatethereof, wherein R⁸ and R⁹ are each C₁ alkyl optionally substituted byR¹⁰.
 82. The compound of claim 80 or 81, or a salt or solvate thereof,wherein R¹⁰ is C₆-C₁₄ aryl.
 83. The compound of claim 82, or a salt orsolvate thereof, wherein R¹⁰ is phenyl.
 84. The compound of claim 1, ora salt or solvate thereof, wherein the compound is of the formula(IIa-1b-2):

or a salt or solvate thereof.
 85. The compound of claim 84, or a salt orsolvate thereof, wherein R² and R³ are independently hydrogen or C₁-C₆alkyl.
 86. The compound of claim 85, or a salt or solvate thereof,wherein R² and R³ are independently hydrogen or methyl.
 87. The compoundof any one of claims 84 to 86, or a salt or solvate thereof, wherein R⁸and R⁹ are independently C₁-C₆ alkyl.
 88. The compound of claim 87, or asalt or solvate thereof, wherein R⁸ and R⁹ are each methyl.
 89. Thecompound of claim 1, or a salt or solvate thereof, wherein the compoundis of the formula (IIa-1c-1):

or a salt or solvate thereof.
 90. The compound of claim 89, or a salt orsolvate thereof, wherein R² and R³ are independently hydrogen or C₁-C₆alkyl.
 91. The compound of claim 90, or a salt or solvate thereof,wherein R² and R³ are independently hydrogen or methyl.
 92. The compoundof any one of claims 89 to 91, or a salt or solvate thereof, wherein R⁸and R⁹ are independently C₁-C₆ alkyl.
 93. The compound of claim 92, or asalt or solvate thereof, wherein R⁸ and R⁹ are each ethyl.
 94. Thecompound of any one of claims 89 to 91, or a salt or solvate thereof,wherein R⁸ and R⁹ are taken together with the nitrogen atom to whichthey are attached to form a 3-12-membered heterocyclyl.
 95. The compoundof claim 94, or a salt or solvate thereof, wherein R⁸ and R⁹ are takentogether with the nitrogen atom to which they are attached to form a4-membered heterocyclyl.
 96. The compound of claim 1, or a salt orsolvate thereof, wherein the compound is of the formula (IIa-1d-2):

or a salt or solvate thereof.
 97. The compound of claim 96, or a salt orsolvate thereof, wherein R² and R³ are each hydrogen.
 98. The compoundof claim 96, or a salt or solvate thereof, wherein R⁹ is C₁-C₆ alkyl.99. The compound of claim 98, or a salt or solvate thereof, wherein R⁹is methyl.
 100. The compound of claim 1, or a salt or solvate thereof,wherein the compound is of the formula (IIa-1e-2):

or a salt or solvate thereof.
 101. The compound of claim 100, or a saltor solvate thereof, wherein R² and R³ are independently C₁-C₆ alkyl.102. The compound of claim 101, or a salt or solvate thereof, wherein R²and R³ are each methyl.
 103. The compound of any one of claims 100 to102, or a salt or solvate thereof, wherein R⁹ is C1-C₆ alkyl.
 104. Thecompound of claim 103, or a salt or solvate thereof, wherein R⁹ ismethyl.
 105. The compound of claim 1, or a salt or solvate thereof,wherein the compound is of the formula (IIa-1f-2):

or a salt or solvate thereof.
 106. The compound of claim 105, or a saltor solvate thereof, wherein R² and R³ are independently C₁-C₆ alkyl.107. The compound of claim 106, or a salt or solvate thereof, wherein R²and R³ are each methyl.
 108. The compound of any one of claims 105 to107, or a salt or solvate thereof, wherein R⁹ is C₁-C₆ alkyl.
 109. Thecompound of claim 108, or a salt or solvate thereof, wherein R⁹ ismethyl.
 110. The compound of claim 1, or a salt or solvate thereof,wherein the compound is of the formula (VIII-a-2):

or a salt or solvate thereof.
 111. The compound of claim 110, or a saltor solvate thereof, wherein V is a bond.
 112. The compound of claim 110or 111, or a salt or solvate thereof, wherein n is
 0. 113. The compoundof any one of claims 110 to 112, or a salt or solvate thereof, wherein kis
 2. 114. The compound of any one of claims 110 to 113, or a salt orsolvate thereof, wherein R⁸ and R⁹ are independently C₁-C₆ alkyl. 115.The compound of claim 114, or a salt or solvate thereof, wherein R⁸ andR⁹ are each methyl.
 116. The compound of claim 1, wherein the compoundis selected from the group consisting of Compound Nos. 1-56 in Table 1,or a salt or solvate thereof.
 117. The compound of claim 1, wherein thecompound is selected from the group consisting of Compound Nos. 57-76 inTable 1-A, or a salt or solvate thereof.
 118. The compound of claim 1,wherein the compound is selected from the group consisting of:1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-(dimethylamino)propyl)piperidine-4-carboxamide,N-(3-(dimethylamino)propyl)-1-(2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide,2-(1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)-N-(3-(dimethylamino)propyl)acetamide,1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(2-(dimethylamino)ethyl)piperidine-4-carboxamide,N-(3-(benzyl(methyl)amino)propyl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide,(4-benzylpiperazin-1-yl)(1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidin-4-yl)methanone,N-(1-benzylazetidin-3-yl)-1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)piperidine-4-carboxamide,and1-(3,4-dimethyl-2-(p-tolyl)-2H-pyrazolo[3,4-d]pyridazin-7-yl)-N-(3-morpholinopropyl)piperidine-4-carboxamide,or a salt thereof.
 119. A pharmaceutical composition comprising acompound of any one of claims 1 to 118, or a salt or solvate thereof,and a pharmaceutically acceptable excipient.
 120. A kit comprising acompound of any one of claims 1 to 118, or a pharmaceutically acceptablesalt thereof.
 121. A pharmaceutical composition comprising apharmaceutically acceptable excipient and a compound of formula (I):

or a salt or solvate thereof, wherein: A¹ is C or N; A² is CR², N orNR^(2a); A³ is CR³⁰, N or NR^(3a); A⁴ is N or CR⁴; A⁵ is N or CR⁵;provided that two, three or four of A¹, A², A³, A⁴ and A⁵ are N; whereinthe dashed lines indicate partial or delocalized bonds in an aromaticring; i and j are independently 0, 1 or 2; R¹ is C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or 3-12-memberedheterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A); each R², R³, R³⁰, R⁴and R⁵ is independently hydrogen, halogen, C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or 3-12-memberedheterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A); each R^(2a) and R^(3a)is independently hydrogen, C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl or 3-12-membered heterocyclyl; wherein theC₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl and3-12-membered heterocyclyl are independently optionally substituted byR^(10A); each R⁶, where present, is independently C₁-C₆ alkyl optionallysubstituted by R^(10A); n is 0, 1, 2, 3 or 4; U is a bond or methyleneoptionally substituted by R¹⁰; V is a bond or C₁-C₂ alkylene optionallysubstituted by R¹⁰; W is a bond or C₁-C₄ alkylene optionally substitutedby one or both of R^(W1) and R^(W2); X is —CR^(X1)R^(X2)—; Y is—CR^(Y1)R^(Y2)—; R⁷ is hydrogen, C₁-C₆ alkyl, or taken together with R⁸to form an ethylene optionally substituted by R¹⁰, or taken togetherwith R^(Y1), R^(X1) or R^(W1), where present, to form a C₁-C₆ alkyleneoptionally substituted by R¹⁰; R⁸ is hydrogen, C₁-C₆ alkyl optionallysubstituted by R¹⁰, C₆-C₁₄ aryl, 5-10-membered heteroaryl, or takentogether with R⁷ to form an ethylene optionally substituted by R¹⁰, ortaken together with R^(Y1), R^(Y2), R^(X1), R^(X2), or R^(W1), wherepresent, to form a C₁-C₆ alkylene optionally substituted by R¹⁰, ortaken together with R¹⁰, where present, to form a C₁-C₆ alkylene, ortaken together with R⁹ and the nitrogen atom to which they are attachedto form a 3-12-membered heterocyclyl optionally substituted by R¹⁰ or a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(Y1), R^(Y2), R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R^(X1), R^(X2), R^(Y1), R^(Y2), R⁹ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(W1), R^(W2),where present, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁹ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰; R⁹ is hydrogen, C₁-C₆ alkyl optionally substitutedby R¹⁰, or taken together with R⁸ and the nitrogen atom to which theyare attached to form a 3-12-membered heterocyclyl optionally substitutedby R¹⁰ or a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(Y1), R^(Y2), R⁸ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(W1), R^(W2),where present, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰; R^(W1), where present, is C₁-C₆ alkyl optionallysubstituted by R^(10A), or taken together with R⁷, R⁸, R^(X1) or R^(Y1)to form a C₁-C₆ alkylene optionally substituted by R¹⁰, or takentogether with R^(W2), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰; R^(W2), where present, is C₁-C₆ alkyloptionally substituted by R^(10A), or taken together with R^(W1),R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰; R^(X1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A),or taken together with R⁷, R⁸, R^(Y1) or R^(W1), where present, to forma C₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attachedto form a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(W1), R^(W2), where present, R^(X2), R^(Y1),R^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰; R^(X2) ishydrogen or C₁-C₆ alkyl optionally substituted by R^(10A), or takentogether with R^(X1), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R⁸ to form a C₁-C₆ alkylene optionally substituted by R¹⁰;R^(Y1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), ortaken together with R⁷, R⁸, R^(X1) or R^(W1), where present, to form aC₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(X1), R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰; R^(Y2) ishydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), or takentogether with R^(Y1), R⁸, R⁹ and the atoms to which they are attached toform a 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(X)1, R^(X2), R^(Y1), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(X2), R^(Y1), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R⁸ to form a C₁-C₆ alkylene optionally substituted by R¹⁰;each R¹⁰ is independently C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl,C₃-C₈ cycloalkyl, 3-12-membered heterocyclyl, 5-10-membered heteroaryl,C₆-C₁₄ aryl, halogen, —CN, —OR¹¹, —SR¹, —NR¹²R¹³, —NO₂, —C═NH(OR¹¹),—C(O)R¹¹, —OC(O)R¹¹, —C(O)OR¹¹, —C(O)NR¹²R¹³, —NR¹¹C(O)R¹²,—NR¹¹C(O)OR¹², —NR¹¹C(O)NR¹²R¹³, —S(O)R¹¹, —S(O)₂R¹¹, —NR¹¹S(O)R¹²,—NR¹¹S(O)₂R¹², —S(O)NR¹²R¹³, —S(O)₂NR¹²R¹³, or —P(O)(OR¹²⁾ (OR¹³);wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl,3-12-membered heterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl ofR¹⁰ are independently optionally substituted by halogen, —CN, oxo,—OR¹⁴, —SR¹⁴, —NR¹⁴R¹⁵, —C(O)R¹⁴, —C(O)OR¹⁴, —S(O)R¹⁴, —S(O)₂R¹⁴,—P(O)(OR¹⁴)(OR¹⁵), 3-12-membered heterocyclyl, 5-10-membered heteroaryl,C₆-C₁₄ aryl, C₃-C₈ cycloalkyl, or C₁-C₆ alkyl optionally substituted byoxo, —OH or halogen, or taken together with R⁸ to form a C₁-C₆ alkylene;each R^(10A) is independently oxo or R¹⁰; R¹¹ is independently hydrogen,C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄aryl, 5-6-membered heteroaryl or 3-6-membered heterocyclyl, wherein theC₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄aryl, 5-6-membered heteroaryl and 3-6-membered heterocyclyl of R¹¹ areindependently optionally substituted by halogen, oxo, —CN, —OR¹⁶,—NR¹⁶R¹⁷, —P(O)(OR¹⁶ (OR¹⁷), or C₁-C₆ alkyl optionally substituted byhalogen, —OH or oxo; R¹² and R¹³ are each independently hydrogen, C₁-C₆alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl,5-6-membered heteroaryl or 3-6 membered heterocyclyl, wherein the C₁-C₆alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₆-C₁₄ aryl,5-6-membered heteroaryl and 3-6 membered heterocyclyl of R¹² and R¹³ areindependently optionally substituted by halogen, oxo, —CN, —OR¹⁶,—NR¹⁶R¹⁷ or C₁-C₆ alkyl optionally substituted by halogen, —OH or oxo;or R¹² and R¹³ are taken together with the atom to which they attachedto form a 3-6 membered heterocyclyl optionally substituted by halogen,oxo, —OR¹⁶, —NR¹⁶R¹⁷ or C₁-C₆ alkyl optionally substituted by halogen,oxo or —OH; R¹⁴ and R¹⁵ are each independently hydrogen, C₁-C₆ alkyloptionally substituted by halogen or oxo, C₂-C₆ alkenyl optionallysubstituted by halogen or oxo, or C₂-C₆ alkynyl optionally substitutedby halogen or oxo; or R¹⁴ and R¹⁵ are taken together with the atom towhich they attached to form a 3-6 membered heterocyclyl optionallysubstituted by halogen, oxo or C₁-C₆ alkyl optionally substituted byhalogen or oxo; and R¹⁶ and R¹⁷ are each independently hydrogen, C₁-C₆alkyl optionally substituted by halogen or oxo, C₂-C₆ alkenyl optionallysubstituted by halogen or oxo, or C₂-C₆ alkynyl optionally substitutedby halogen or oxo; or R¹⁶ and R¹⁷ are taken together with the atom towhich they attached to form a 3-6 membered heterocyclyl optionallysubstituted by halogen, oxo or C₁-C₆ alkyl optionally substituted by oxoor halogen; provided that when R⁸ and R⁹ are taken together with thenitrogen atom to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, and the 5-10-memberedheteroaryl is a fused ring heteroaryl comprising an aryl moiety fused toa heterocycle containing the nitrogen atom to which R⁸ and R⁹ areattached, the aryl moiety is not adjacent to the nitrogen atom to whichR⁸ and R⁹ are attached.
 122. A method of inhibiting a toll-like receptor8 (TLR8)-dependent response, comprising administering the pharmaceuticalcomposition of claim 119 or 121 to an individual in an amount effectiveto inhibit the TLR8-dependent response in the individual.
 123. A methodof inhibiting a toll-like receptor 9 (TLR9)-dependent response,comprising administering the pharmaceutical composition of claim 119 or121 to an individual in an amount effective to inhibit theTLR9-dependent response in the individual.
 124. A method of inhibitingboth a TLR8-dependent response and a TLR9-dependent response, comprisingadministering the pharmaceutical composition of claim 119 or 121 to anindividual in an amount effective to inhibit the TLR8-dependent responseand the TLR9-dependent response in the individual.
 125. A method ofinhibiting an immune response, comprising administering thepharmaceutical composition of claim 119 or 121 to an individual in anamount effective to inhibit the immune response in the individual. 126.The method of claim 125, wherein the immune response comprises aTLR8-dependent immune response.
 127. The method of claim 125, whereinthe immune response comprises a TLR9-dependent immune response.
 128. Themethod of claim 125, wherein the immune response comprises both aTLR8-dependent immune response and a TLR9-dependent immune response.129. The method of claim 125, wherein the immune response is associatedwith an immunological disorder.
 130. The method of claim 129, whereininhibiting the immune response ameliorates one or more symptoms of theimmunological disorder
 131. The method of claim 129 or 130, furthercomprising administering a second therapeutic agent to the individual.132. The method of claim 131, wherein the second therapeutic agent isselected from the group consisting of a nonsteroidal anti-inflammatorydrug, a corticosteroid, an antimalarial drug, an immunosuppressive drug,and a biologic.
 133. The method of any one of claims 129 to 132, whereinthe immunological disorder is an autoimmune disease.
 134. The method ofclaim 133, wherein the autoimmune disease is selected from the groupconsisting of systemic lupus erythematosus, type I diabetes mellitus,multiple sclerosis, rheumatoid arthritis, inflammatory bowel disease,Sjogren's syndrome, scleroderma and dermatomyositis.
 135. The method ofclaim 134, wherein the inflammatory bowel disease is selected from thegroup consisting of Crohn's disease and ulcerative colitis.
 136. Themethod of any one of claims 129 to 132, wherein the immunologicaldisorder is an inflammatory disease.
 137. The method of claim 136,wherein the inflammatory disease is selected from the group consistingof pancreatitis, kidney fibrosis, liver fibrosis, lung fibrosis, chronickidney disease, alcohol-related fatty liver disease, non-alcoholic fattyliver disease, and liver cirrhosis.
 138. The method of claim 125,wherein the immune response is associated with chronic pathogenstimulation.
 139. The method of claim 125, wherein the immune responseis associated with acute pathogen stimulation.
 140. The method of claim139, wherein the acute pathogen stimulation is due to sepsis.
 141. Amethod of treating cancer, comprising administering the pharmaceuticalcomposition of claim 119 or 121 to an individual with cancer in anamount effective to treat the cancer.
 142. The method of claim 141,wherein the cancer is dependent upon activation of one or both of TLR8and TLR9.
 143. The method of claim 142, wherein the cancer is activatedB cell type-diffuse large B cell lymphoma.
 144. The method of claim 142,wherein the cancer is Waldenstrom's macroglobulinemia.
 145. The methodof claim 142, wherein cells of the cancer possess an oncogenic mutationin a myeloid differentiation primary response gene 88 (MYD88).
 146. Themethod of claim 142, wherein the cancer is hepatocellular carcinoma(HCC).
 147. The method of any one of claims 122 to 146, wherein theindividual is human.
 148. A compound of formula (I):

or a salt or solvate thereof, wherein: A¹ is C or N; A² is CR², N orNR^(2a); A³ is CR³⁰, N or NR^(3a); A⁴ is N or CR⁴; A⁵ is N or CR⁵;provided that two, three or four of A¹, A², A³, A⁴ and A⁵ are N; whereinthe dashed lines indicate partial or delocalized bonds in an aromaticring; i and j are independently 0, 1 or 2; R¹ is C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or 3-12-memberedheterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A); each R², R³, R³⁰, R⁴and R⁵ is independently hydrogen, halogen, C₁-C₆ alkyl, C₃-C₈cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl or 3-12-memberedheterocyclyl; wherein the C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl and 3-12-membered heterocyclyl areindependently optionally substituted by R^(10A); each R^(2a) and R^(3a)is independently hydrogen, C₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl,5-10-membered heteroaryl or 3-12-membered heterocyclyl; wherein theC₁-C₆ alkyl, C₃-C₈ cycloalkyl, C₆-C₁₄ aryl, 5-10-membered heteroaryl and3-12-membered heterocyclyl are independently optionally substituted byR^(10A); each R⁶, where present, is independently C₁-C₆ alkyl optionallysubstituted by R^(10A); n is 0, 1, 2, 3 or 4; U is a bond or methyleneoptionally substituted by R¹⁰; V is a bond or C₁-C₂ alkylene optionallysubstituted by R¹⁰; W is a bond or C₁-C₄ alkylene optionally substitutedby one or both of R^(W1) and R^(W2); X is —CR^(X1)R^(X2)—; Y is—CR^(Y1)R^(Y2)—; R⁷ is hydrogen, C₁-C₆ alkyl, or taken together with R⁸to form an ethylene optionally substituted by R¹⁰, or taken togetherwith R^(Y1), R^(X1) or R^(W1), where present, to form a C₁-C₆ alkyleneoptionally substituted by R¹⁰; R⁸ is hydrogen, C₁-C₆ alkyl optionallysubstituted by R¹⁰, or taken together with R⁷ to form an ethyleneoptionally substituted by R¹⁰, or taken together with R^(Y1), R^(X1) orR^(W1), where present, to form a C₁-C₆ alkylene optionally substitutedby R¹⁰, or taken together with R⁹ and the nitrogen atom to which theyare attached to form a 3-12-membered heterocyclyl optionally substitutedby R¹⁰ or a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(Y1), R^(Y2), R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R^(X1), R^(X2), R^(Y1), R^(Y2), R⁹ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(W1), R^(W2),where present, R^(X)1, R^(X2), R^(Y1), R^(Y2), R⁹ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰; R⁹ is hydrogen, C₁-C₆ alkyl optionally substitutedby R¹⁰, or taken together with R⁸ and the nitrogen atom to which theyare attached to form a 3-12-membered heterocyclyl optionally substitutedby R¹⁰ or a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(Y1), R^(Y2), R⁸ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰, or taken together with R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰, or taken together with R^(W1), R^(W2),where present, R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸ and the atoms to whichthey are attached to form a 5-10-membered heteroaryl optionallysubstituted by R¹⁰; R^(W1), where present, is C₁-C₆ alkyl optionallysubstituted by R^(10A), or taken together with R⁷, R⁸, R^(X1) or R^(Y1)to form a C₁-C₆ alkylene optionally substituted by R¹⁰, or takentogether with R^(W2), R^(X1), R^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and theatoms to which they are attached to form a 5-10-membered heteroaryloptionally substituted by R¹⁰; R^(W2), where present, is C₁-C₆ alkyloptionally substituted by R^(10A), or taken together with R^(W1),R^(X1), R^(X2), R^(Y)1, R^(Y2), R⁸, R⁹ and the atoms to which they areattached to form a 5-10-membered heteroaryl optionally substituted byR¹⁰; R^(X1) is hydrogen, C₁-C₆ alkyl optionally substituted by R^(10A),or taken together with R⁷, R⁸, R^(Y1) or R^(W1), where present, to forma C₁-C₆ alkylene optionally substituted by R¹⁰, or taken together withR^(X2), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attachedto form a 5-10-membered heteroaryl optionally substituted by R¹⁰, ortaken together with R^(W1), R^(W2), where present, R^(X2), R^(Y1),R^(Y2), R⁸, R⁹ and the atoms to which they are attached to form a5-10-membered heteroaryl optionally substituted by R¹⁰; R^(X2) ishydrogen or C₁-C₆ alkyl optionally substituted by R^(10A), or takentogether with R^(X), R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which theyare attached to form a 5-10-membered heteroaryl optionally substitutedby R¹⁰, or taken together with R^(W1), R^(W2), where present, R^(X1),R^(Y1), R^(Y2), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰; R^(Y1) ishydrogen, C₁-C₆ alkyl optionally substituted by R^(10A), or takentogether with R⁷, R⁸, R^(X1) or R^(W1), where present, to form a C₁-C₆alkylene optionally substituted by R¹⁰, or taken together with R^(Y2),R⁸, R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, or taken together with R^(X1),R^(X2), R^(Y2), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(W1), R^(W2), where present, R^(X1), R^(X2), R^(Y2), R⁸,R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰; R^(Y2) is hydrogen, C₁-C₆alkyl optionally substituted by R^(10A), or taken together with R^(Y1),R⁸, R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰, or taken together with R^(X1),R^(X2), R^(Y1), R⁸, R⁹ and the atoms to which they are attached to forma 5-10-membered heteroaryl optionally substituted by R¹⁰, or takentogether with R^(W1), R^(W2), where present, R^(X1), R^(X2), R^(Y1), R⁸,R⁹ and the atoms to which they are attached to form a 5-10-memberedheteroaryl optionally substituted by R¹⁰; each R¹⁰ is independentlyC₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl,3-12-membered heterocyclyl, 5-10-membered heteroaryl, C₆-C₁₄ aryl,halogen, —CN, —OR¹¹, —SR¹¹, —NR¹²R¹³, —NO₂, —C═NH(OR¹¹), —C(O)R¹¹,—OC(O)R^(u), —C(O)OR¹¹, —C(O)NR¹²R¹³, —NR¹¹C(O)R¹², —NR¹¹C(O)OR¹²,—NR¹¹C(O)NR¹²R¹³, —S(O)R, —S(O)₂R¹¹, —NR¹¹S(O)R¹², —NR¹¹S(O)₂R¹²,—S(O)NR¹²R¹³, —S(O)₂NR¹²R¹³, or —P(O)(OR¹²) (OR¹³); wherein the C₁-C₆alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₈ cycloalkyl, 3-12-memberedheterocyclyl, 5-10-membered heteroaryl and C₆-C₁₄ aryl of R¹⁰ areindependently optionally substituted by halogen, —CN, oxo, —OR¹⁴, —SR¹⁴,—NR¹⁴R¹⁵, —C(O)R¹⁴, —C(O)OR¹⁴, —S(O)R¹⁴, —S(O)₂R¹⁴, —P(O)(OR¹⁴)(OR¹⁵),3-12-membered heterocyclyl, 5-10-membered heteroaryl, C₆-C₁₄ aryl, C₃-C₈cycloalkyl, or C₁-C₆ alkyl optionally substituted by oxo, —OH orhalogen; each R^(10A) is independently oxo or R¹⁰; R¹¹ is independentlyhydrogen, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₆-C₁₄ aryl, 5-6-membered heteroaryl or 3-6-membered heterocyclyl,wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₆-C₁₄ aryl, 5-6-membered heteroaryl and 3-6-membered heterocyclyl ofR¹¹ are independently optionally substituted by halogen, oxo, —CN,—OR¹⁶, —NR¹⁶R¹⁷, —P(O)(OR¹⁶ (OR¹⁷), or C₁-C₆ alkyl optionallysubstituted by halogen, —OH or oxo; R¹² and R¹³ are each independentlyhydrogen, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₆-C₁₄ aryl, 5-6-membered heteroaryl or 3-6 membered heterocyclyl,wherein the C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₆-C₁₄ aryl, 5-6-membered heteroaryl and 3-6 membered heterocyclyl ofR¹² and R¹³ are independently optionally substituted by halogen, oxo,—CN, —OR¹⁶, —NR¹⁶R¹⁷ or C₁-C₆ alkyl optionally substituted by halogen,—OH or oxo; or R¹² and R¹³ are taken together with the atom to whichthey attached to form a 3-6 membered heterocyclyl optionally substitutedby halogen, oxo, —OR¹⁶, —NR¹⁶R¹⁷ or C₁-C₆ alkyl optionally substitutedby halogen, oxo or —OH; R¹⁴ and R¹⁵ are each independently hydrogen,C₁-C₆ alkyl optionally substituted by halogen or oxo, C₂-C₆ alkenyloptionally substituted by halogen or oxo, or C₂-C₆ alkynyl optionallysubstituted by halogen or oxo; or R¹⁴ and R¹ are taken together with theatom to which they attached to form a 3-6 membered heterocyclyloptionally substituted by halogen, oxo or C₁-C₆ alkyl optionallysubstituted by halogen or oxo; and R¹⁶ and R¹⁷ are each independentlyhydrogen, C₁-C₆ alkyl optionally substituted by halogen or oxo, C₂-C₆alkenyl optionally substituted by halogen or oxo, or C₂-C₆ alkynyloptionally substituted by halogen or oxo; or R¹⁶ and R¹⁷ are takentogether with the atom to which they attached to form a 3-6 memberedheterocyclyl optionally substituted by halogen, oxo or C₁-C₆ alkyloptionally substituted by oxo or halogen; provided that when R⁸ and R⁹are taken together with the nitrogen atom to which they are attached toform a 5-10-membered heteroaryl optionally substituted by R¹⁰, and the5-10-membered heteroaryl is a fused ring heteroaryl comprising an arylmoiety fused to a heterocycle containing the nitrogen atom to which R⁸and R⁹ are attached, the aryl moiety is not adjacent to the nitrogenatom to which R⁸ and R⁹ are attached; and provided that the compound isother than Compound Nos. 1x-82x in Table 1X and salts thereof.